Post on 15-Sep-2019
2013 edition – for use in England*
Incorporating 2018 amendments
Domestic Building Services Compliance Guide
ONL INE VERS ION
ONL INE VERS ION
* Note: Any reference to the Building Regulations in this guide is to the Building Regulations 2010 in England (as amended).
These Regulations also apply in Wales to work on an excepted energy building as defined in the Schedule to the Welsh Ministers (Transfer of Functions) (No. 2) Order 2009 (SI 2009/3019).
The 2018 amendments to the guidance come into effect on 6 April 2018 with the following exceptions where the earlier edition of this guidance continues to apply:
(a) Work started on site before this date;
(b) Work subject to a building notice, full plans application or initial notice submitted before this date provided it is started on site before 1 October 2018; or
(c) Work where a contract for installation was agreed before 6 April 2018 and work is started on site before 1 October 2018.
For other jurisdictions in the UK, it will be necessary to consult their own building regulations and guidance.
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Contents
Contents
Section 1: Introduction 51.0 ChangestothiseditionoftheGuide 5
1.1 Scope 5
1.2 Innovativesystems 5
1.3 Europeandirectives 6
1.4 Statusofguide 7
1.5 Howtousethisguide 8
1.6 Keyterms 8
1.7 Workonexistingsystems 9
1.8 Replacementofprimaryheatingappliances 9
1.9 Summaryofrecommendedminimumenergyefficiencystandards 11
Section 2: Gas-fired space and water heating 142.1 Scopeofguidance 14
2.2 Keyterms 14
2.3 Gas-firedwetcentralheatingsystems 14
2.4 Gas-firedrangecookerswithintegralcentralheatingboiler 21
2.5 Gas-firedwarmairheating 21
2.6 Gas-firedfixedindependentspaceheatingappliances 23
2.7 Gas-firedfixeddecorativefuel-effectfires 25
2.8 Gasfiresforsecondaryspaceheatingprovidedaspartofacombinedfireandbackboilerunit 25
Section 3: Oil-fired space and water heating 273.1 Scopeofguidance 27
3.2 Oil-firedwetcentralheatingsystems 27
3.3 Oil-firedrangecookerswithintegralcentralheatingboilers 34
3.4 Continuously-burningoil-firedvaporisingappliancesprovidingsecondaryheatingorhotwater 35
3.5 Oil-firedfixedindependentspaceheatingappliances 36
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Section 4: Electric heating 374.1 Scopeofguidance 37
4.2 Electricboilersservingcentralheatingsystems 37
4.3 Electricheatingsystems(otherthanelectricboilersservingcentralheating) 41
Section 5: Solid fuel heating 435.1 Scopeofguidance 43
5.2 Solidfuelappliancesforprimaryheating 43
5.3 Centralheatingsystemsusingcertaintypesofsolidfuelappliances 46
5.4 Solidfuelappliancesforsecondaryheating 51
Section 6: Community heating 536.1 Scopeofguidance 53
6.2 Newandexistingcommunityheatingschemes 53
Section 7: Underfloor heating 607.1 Scopeofguidance 60
7.2 Underfloorheatinginnewdwellings 60
Section 8: Mechanical ventilation 648.1 Scopeofguidance 64
8.2 Energyefficiencyofmechanicalventilationsystems 64
Section 9: Heat pumps 659.1 Scopeofguidance 65
9.2 Keyterms 67
9.3 Warmwaterandhotwaterheatpumps 67
Section 10: Comfort cooling 731 0.1 Scopeofguidance 73
10.2 Air-cooledandwater-cooledairconditioners 73
Section 11: Solar water heating 7411.1 Scopeofguidance 74
11.2 Indirectsystems 74
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Section 12: Lighting 8112.1 Scopeofguidance 81
12.2 Keyterms 81
12.3 Internalandexternallighting 81
Section 13: Micro-combined heat and power 8313.1 Scopeofguidance 83
13.2 Keyterms 83
1 3.3 Micro-CHPsystems 83
Section 14: Heating system circulators 851 4.1 Scopeofguidance 85
14.2 Circulators 85
Appendix A: Abbreviations 86
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Section 1: Introduction
Section 1: Introduction
1.0 Changes to this edition of the Guide
The2018amendmentstothisguideintroducerevisedstandardsforwhengas-firedandoil-firedboilersareinstalledorreplacedinexistingdwellings.
ThesechangesaffectSection2andSection3ofthisdocument,andpartsofthisintroductorysection.Nootherchangeshavebeenmade.
1.1 ScopeThisguideprovidesdetailedguidancefortheinstallationoffixedbuildingservicesinnewandexistingdwellingstohelpcompliancewiththeenergyefficiencyrequirementsoftheBuildingRegulations.
Thiseditioncoversthedesign,installationandcommissioningof:
• conventionalmeansofprovidingprimaryandsecondaryspaceheating,domestichotwater,mechanicalventilation,comfortcoolingandinternalandexternallighting
• lowcarbongenerationofheatbyheatpumps,solarthermalpanels,andmicro-combinedheatandpowersystems.
Theguidesetsoutrecommendedminimumenergyefficiencystandardsforcomponentsofbuildingservicessystems,includingtheuseofcontrols.Forsystemsinstalledinnewdwellings,thestandardsaredesignlimits(orbackstopvalues).Forneworreplacementsystemsandcomponentsinstalledinexistingdwellings,thestandardsrepresentreasonableprovisionforcomplyingwiththeBuildingRegulations.
It is important to note that standards higher than many of these recommended minimum standards will need to be achieved if:
• new dwellings are to meet the the Building Regulations target carbon dioxide emission rate (TER) calculated using SAP1
• systems are to comply with the Microgeneration Certification Scheme standards2 that enable building owners to receive payments under the Renewable Heat Incentive (RHI) and qualify for Green Deal funding
• products are to be recognised as renewable technologies under the Renewable Energy Directive.
Theguideincludessomesupplementaryinformationthatidentifiesgoodpracticedesignandinstallationstandardsthatexceedtheminimumstandardsinthisguide.MicrogenerationCertificationSchemestandardsareanexampleofgoodpracticestandards.
AsummaryofrecommendedminimumenergyefficiencystandardsispresentedinTable1attheendofthissection.
1.2 Innovative systemsItisalsoimportanttonotethatthisguidecoversarangeoffrequentlyoccurringsituationsanddealswiththemostcommonlyusedfixedbuildingservicestechnologies.Indoingsoitneitherendorses
1 StandardAssessmentProcedure,www.bre.co.uk/SAP20122 http://www.microgenerationcertification.org/mcs-standards
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thesemethodsandtechnologiesnorexcludesothermoreinnovativetechnologiesthatmayofferanalternativemeansofmeetingthefunctionalrequirementsoftheBuildingRegulations.
Wherethealternativetechnologyhasbeenthesubjectofarecognisedtestingprocedurethatassessesitsenergyperformance,thismaybeusedtoindicatethatthesystemisadequatelyefficient.Intheeventthatthereisnorecognisedtestingstandard,suitablecalculationsormodellingmethodsmaybeusedtoshowthecarbonperformanceofthesystem.
1.3 European directivesThedesignandinstallationoffixedbuildingservicesproducts,suchasboilers,circulatorsandheatpumps,shallattheappropriatetimecomplywithallrelevantrequirementsofEUdirectivesasimplementedintheUnitedKingdom.Thereareanumberofdirectiveswithrequirementsthatdirectlyorindirectlycontroltheenergyefficiencyofbuildingservices.
TheEcodesign Directive2009/125/ECprovidesaframeworkforestablishingrequirementsfor‘energy-related’productsplacedontheEUmarket.Currentrequirementscover‘energy-using’productssuchasboilers,lightbulbsandwashingmachines.Inthefuture,requirementswillalsocoverproductssuchaswindows,insulationmaterialandshowerheadswhoseusehasanimpactonenergyconsumption.
TherequirementsaresetoutinCommissionRegulationslistedinthedocumenthttp://ec.europa.eu/energy/efficiency/ecodesign/doc/overview_legislation_eco-design.pdf.ProductscoveredbytheregulationscanonlybeCEmarkedandplacedonthemarketiftheymeettheecodesignstandardsspecified.
Atthetimeofpreparationofthisguide,CommissionRegulationsexistedorwerebeingdevelopedfor:
• spaceheatersandcombinationheaters
• waterheatersandhotwaterstoragetanks
• glandlessstandalonecirculatorsandglandlesscirculatorsintegratedinproducts
• waterpumps
• airconditionersandcomfortfans
• fansdrivenbymotorswithanelectricinputpowerbetween125Wand500W
• lightingproductsinthedomesticandtertiarysectors
• electricmotors.
TheintentionisthattherecommendedminimumproductstandardsinthisguideshouldatleastmatchtheenergyefficiencystandardssetoutinCommissionRegulationsas they come into force.Forexample,althoughtheimplementingregulationsforhotwaterstoragetankswerepublishedinSeptember2013,thestandardsdonotcomeintoforceuntilSeptember2017.
If in any doubt as to whether a product is subject to minimum ecodesign standards, check the Commission document above.
TheEnergy Labelling Directive 2010/30/EUcomplementstheEcodesignDirectivebyprovidingaframeworkforlabellingofenergy-relatedproductsincludinglamps,luminaires,householdairconditionersandwashingmachines.TheEnergyLabelclassifiesproductsonanAtoGscale,‘pulling’themarkettowardsmoreefficientproductsbybetterinformingconsumers.TheEcodesignDirective,bycontrast,usesregulationto‘push’themarketawayfromtheworstperformingproducts.
TheRenewable Energy Directive 2009/28/ECprovidesaframeworkforthepromotionofenergyfromrenewableresources.ItsetsamandatoryUKtargetof15%energygenerationfromrenewablesourcesby
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Section 1: Introduction
2020–the‘renewableenergyobligation’–asacontributiontomeetingtheEU’soveralltargetof20%.Ofrelevancetobuildingservicesisthatthedirectiveidentifiescriteriafortrainingandcertificationofinstallersofrenewables.ThedirectivealsospecifiesinAnnexVIIthestandardsthatheatpumpsmustachievetoberecognisedasrenewabletechnologiesbythedirective.
TheEnergy Efficiency Directive2012/27/EUestablishesacommonframeworkofmeasuresforthepromotionofenergyefficiencywithintheEUinordertoensurethattheEUmeetsitstargetofa20%reductioninprimaryenergyconsumptionby2020.LegislationtoimplementthedirectiveintheUKwillbepublishedby5June2014.Includedwillberequirementsforpublicauthoritiestopurchaseonlyenergy-efficientproducts,servicesandbuildings;andrequirementsforheatmeterstobefittedinapartmentsandbuildingsconnectedtoacentralsourceofheatingoradistrictheatingnetwork.Formoreinformationonthespecificrequirementsandtechnicalstandards,seetheDECCwebsite3.
TheEnergy Performance of Buildings Directive2010/31/EUisarecastoftheoriginal2002/91/ECdirective,whichin2002introducedrequirementsfor:
• theestablishmentofamethodologyforcalculatingtheintegratedenergyperformanceofbuildings
• minimumenergyperformancerequirementsfornewbuildings,and,wherefeasible,forlargerbuildingsundergoingmajorrenovation
• energyperformancecertificationofbuildings,and
• inspectionsofheatingandairconditioningsystems.
Therecastdirectiveincludesanewrequirementtoconsiderinthedesignofnewbuildingsthefeasibilityofusingrenewablesandother‘high-efficiencyalternativesystems’.Thereisnomandatoryformatforthisassessment,butitwillnowbenecessarytodeclare(throughanewfieldintheenergyperformancecalculationsoftware)thatithasbeencarriedout.
TheBuildingRegulations,whichalreadymettheoriginalrequirementsinmanyways(forexamplebysettingstandardsfornewbuildings),havebeenamendedinsomeplacestoreflectthenewrequirementsofthedirective.Forguidanceonthechangesaffectingnewdwellings,seeApprovedDocumentL1A.Forguidanceonthechangesaffectingmajorrenovations,seeApprovedDocumentL1B.Forguidanceonotherrequirementsrelatingtobuildingcertificationandinspectionofheatingandairconditioningsystems,seetheDCLGwebsite4.
1.4 Status of guideTheBuildingRegulationscontainfunctionalrequirements,suchasrequirementsthatbuildingsmustbestructurallystable,constructedandfittedtoensurefireprotection,andenergyefficient.Thesefunctionalrequirementsareoftendraftedinbroadterms,andsoitmaynotalwaysbeimmediatelycleartoapersoncarryingoutworkhowtocomplywiththerelevantrequirements.Consequently,theDepartmentforCommunitiesandLocalGovernmentissuesdocuments,knownasapproveddocuments,whichprovidepracticalguidanceonwaysofcomplyingwithspecificaspectsoftheBuildingRegulationsinsomeofthemorecommonbuildingsituations.
Approveddocumentsarenotalwayscomprehensiveandmaycontainreferencestootherdocumentswhichwillprovidemoredetailedinformationandassistanceonpartsoftheguidance.Thisguideisoneofthosedocuments:itprovidesmoredetailedinformationontheguidancecontainedinApprovedDocumentsL1AandL1Baboutcompliancewiththeenergyefficiencyrequirementswhichapplywheninstallingfixedbuildingservicesinnewandexistingdwellings.
3 https://www.gov.uk/decc4 https://www.gov.uk/dclg
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Ifyoufollowtherelevantguidanceinanapproveddocument,andinanydocumentreferredtointheapproveddocument(suchasthisguide)whichprovidesadditionalinformationtohelpyoufollowthatguidance,thereisalegalpresumptionthatyouhavecompliedwiththeBuildingRegulations.However,ineachcaseitisforthebuildingcontrolbody(localauthorityorapprovedinspector)todecidewhetherworkcomplieswiththerequirementsoftheBuildingRegulations.ItisthereforesensiblethatyoucheckwiththebuildingcontrolbodybeforestartingworkwhattheyconsideritisnecessaryforyoutodotocomplywiththerequirementsoftheBuildingRegulations.
1.5 How to use this guideTheguidecomprisesfourfuel-basedsectionsandninetechnology-specificsections:
• Fuel-based
Section2:Gas-firedspaceandwaterheating
Section3:Oil-firedspaceandwaterheating
Section4:Electricheating
Section5:Solidfuelheating
• Technology-specific
Section6:Communityheating
Section7:Underfloorheating
Section8:Mechanicalventilation
Section9:Heatpumps
Section10:Comfortcooling
Section11:Solarwaterheating
Section12:Lighting
Section13:Micro-combinedheatandpower
Section14:Heatingsystemcirculators
Foranyparticularapplication,referencemayneedtobemadetomorethanonesection.
Supplementaryinformationisshownagainstabluebackground.ThismaybefurtherinformationtohelpwithinterpretingtheminimumenergyefficiencyprovisionsneededtocomplywiththeBuildingRegulations.Oritmaybeguidanceonbestpracticethatgoesbeyondtherecommendedminimumstandards.
Keytermsareprintedinblueatappropriatepointsthroughouttheguide.
1.6 Key termsFixedbuildingservicesmeansanypartof,oranycontrolsassociatedwith:
a. fixedinternalorexternallightingsystems,butdoesnotincludeemergencyescapelightingorspecialistprocesslighting
b. fixedsystemsforheating,domestichotwater,airconditioningormechanicalventilation,or
c. anycombinationofsystemsofthekindsreferredtoinsub-paragrapha.orb.
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Section 1: Introduction
Newsystemmeansafixedbuildingservicessysteminstalled:
a. inanewbuilding
b. forthefirsttimeinanexistingbuilding
c. asacompletereplacementforasysteminanexistingbuilding.
SeasonalefficiencymeanstheefficiencyvalueusedbySAPforaheatingappliance.Forgas,LPGandoilboilersthathavebeentestedforefficiency,thisisSEDBUK5.Forgasboilersinstalledinexistingbuildings,thisisErP 6.
1.7 Work on existing systemsArequirementoftheBuildingRegulationsisthatworkonexistingbuildingsshouldbecarriedoutinsuchawaythatwhentheworkiscomplete:
a. theworkitselfcomplieswiththeapplicablerequirementsoftheBuildingRegulations
b. thepartsofthebuildingnotaffectedbytheworkarenomoreunsatisfactoryinrelationtotherequirementsoftheRegulationsthanbeforetheworkwasstarted.
Thismeansthatwhenasystemcomponentlikearoomthermostatisreplaced,onlythenewcomponentisexpectedtocomplywiththestandardsinthisguide(whichinsomecasesmaybelowerthanfornewsystems).
Whenreplacingaboiler,theboilercontrolsareconsideredtobepartoftheboilerinstallationandshouldthereforemeetthestandardssetoutintherelevantsectionsofthisdocument.Forgas-firedcombinationboilers,certainenergyefficiencymeasuresarealsoconsideredtobepartoftheboilerinstallationandshouldmeetthestandardssetoutinSection3.
Itisnotageneralrequirementtoupgradetherestoftheexistingsystem,butthisguidedoesincludesomerecommendationsonminorupgradesforcompliancewiththeBuildingRegulationswheretheywouldbecost-effectiveandmaybenecessarytoensureefficientoperationofthenewcomponent.
Someofthesupplementaryinformationisguidanceongoodpracticethat,whilenotessentialforcompliancewiththeBuildingRegulations,wouldhelptosaveenergy.Forexample,itisconvenientandtimelytofitthermostaticradiatorvalveswhenreplacingaboilerandthesystemhasbeendraineddown.
1.8 Replacement of primary heating appliancesWhenreplacinganexistingappliance,theefficiencyofthenewapplianceshouldnotbesignificantlylessthantheefficiencyoftheappliancebeingreplaced.Ifthereplacementinvolvesafuelswitch,thentherelativecarbonemissionsassociatedwiththenewandexistingfuelsshouldbeconsideredwhenassessingthereasonablenessoftheproposednewappliance.Theaimistodiscouragereplacementofanexistingappliancebyasignificantlylesscarbonefficientone.
Forgas-firedboilers 7,aminimumenergyefficiencystandardappliestothereplacementappliance.Forgasandoil-firedboilers,theinstallationofareplacementapplianceshouldalsoincludeadequatecontrols.Forgas-firedcombinationboilers,theinstallationofareplacementapplianceshouldalsoincludeadditionalenergyefficiencymeasures.FulldetailsoftheserequirementscanbefoundinSection2forgas-firedboilersandSection3foroil-firedboilers.
5 TheSAPProductCharacteristicsDatabase(PCDB)atwww.ncm-pcdb.org.uk/sapdisplaysseparateSAPwinterandsummerseasonalefficienciesforboilersheldwithinit.SAP2012(availableatwww.bre.co.uk/sap2012)usesthesevaluestocalculatethecarbondioxideemissionrateforadwelling.SAPwinterandsummerseasonalefficienciesarederivedfromSEDBUK2009values.
6 ReferstotheefficiencymethodologysetoutinDirective2009/125/ECforenergyperformancerelatedproducts.7 Exceptheatingboilersthatarecombinedwithrangecookers.
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Replacement not involving fuel or energy switch
Wheretheprimaryheatingapplianceisreplacedbyoneusingthesamefuelorenergysupply,theseasonalefficiencyofthenewequipmentshouldbe:
a. asstatedintherelevantfuel-basedsectionofthisguide,and
b. notworsethan2percentagepointslowerthantheseasonalefficiencyofthecontrolledservicebeingreplaced.Iftheefficiencyoftheappliancetobereplacedisnotknown,efficiencyvaluesmaybetakenfromTable4aor4bofSAP2012.
Replacement involving fuel or energy switch
Ifthenewheatingapplianceusesadifferentfuel,theefficiencyofthenewserviceshouldbemultipliedbytheratioofthecarbondioxideemissionfactorofthefuelusedintheservicebeingreplacedtothatofthefuelusedinthenewservice,toobtainthe‘carbonequivalentefficiency’.Thechecksdescribedinsub-paragraphsa.andb.aboveshouldthenbemade.ThecarbondioxideemissionfactorsshouldbetakenfromTable12ofSAP2012.
Electric flow boilers
Itwillnotnormallybepossibletoreplaceagasboilerwithanelectricflowboilerandmeetthestandardaboveforreplacementsinvolvinganenergyswitch.However,ifitisnotpracticableorpermissibletofitareplacementgasboilerinadwelling–forexamplebecausetheboilerinstallationwouldnotcomplywithrelevantBritishStandardsortheBuildingRegulations,orlistedbuildingconsenthasnotbeengrantedtoinstallanewflueorgassupply–then,providedthereisnopossiblealternative,fittinganelectricflowboilerinaccordancewiththeguidanceonelectricheatingsystemsinSection4ofthisguidewouldbeacceptable,andcountasmaking‘reasonableprovision’forthepurposesofcomplyingwiththerequirementsoftheBuildingRegulations.
Example
Anoldoil-firedboilerwithaseasonalefficiencyof72%istobereplacedbyadualsolidfuelboiler.Thenewdualsolidfuelboilershouldhave:
a. aseasonalefficiencynotlessthan65%(fromTable21inthisguide),and
b. acarbonequivalentefficiencynotlessthan70%.
Adualsolidfuelboilerwithaseasonalefficiencyof65%willmeetconditionb.asitscarbonequivalentefficiencyis:
65%(0.2980.226)85.7%
where0.298and0.226kgCO2/kWharetheemissionfactorsforoilanddualsolidfuelsrespectively.
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1.9 Summary of recommended minimum energy efficiency standards
Table 1 Recommended minimum energy efficiency standards for building services8
Gas-fired wet central heating
Seasonal efficiency
SEDBUK 20099SEDBUK 2005/SEDBUK ErP10
Condensingboilersinnewdwellings 88% 90% -
Condensingboilersinexistingdwellings - - 92%
Non-condensingboilers(wherepermitted):naturalgas/LPG 78%/80% 78%/80% -
Rangecookerboilers 75% 75% -
Gas-fired warm air heating Efficiency
SeeTable6
Gas-fired fixed independent space heaters Efficiency (gross)11
GasandLPGprimaryheating 63%
GasandLPGsecondaryheating 63%(newbuild)45%(existingbuild)
Decorativefuel-effect Notspecified(setto20%inSAP2012)
Gas fires in combined fire/backboilers (replacements)
Efficiency (gross)
Natural gas LPG
Insetlivefuel-effect 45% 46%
Alltypesexceptinsetlivefuel-effect 63% 64%
Oil-fired wet central heating
Seasonal efficiency
SEDBUK 2009 SEDBUK 2005/SEDBUK
Condensingregularboilers 88% 90%
Condensingcombinationboilers 86% 86%
Non-condensingregularboilers(wherepermitted) 84% 85%
Non-condensingcombinationboilers(wherepermitted) 82% 82%
Rangecookerboilers 80% 80%
Oil-fired appliances Efficiency (gross)
Continuously-burningvaporisingforsecondaryheatingorhotwater SeeSection3.4
Fixedindependentforprimaryandsecondaryspaceheating 60%
Electric heating Efficiency
Boilersservingcentralheating N/A
Warmair N/A
8 EmergingEuropeanregulationsimplementingtheEcodesignDirectivewillsetminimumstandardsfortheefficiencyofenergy-usingproductsthatcanbeplacedonthemarket.Productsshouldalsocomplywiththesestandardsastheycomeintoeffect.Currentregulationsarelistedathttp://ec.europa.eu/energy/efficiency/ecodesign/doc/overview_legislation_eco-design.pdf.
9 SeasonalEfficiencyofDomesticBoilersintheUK(SEDBUK).TheboilerefficiencyshouldmeeteithertheSEDBUK2009orSEDBUK2005standard.IftheSEDBUKefficiencyinaboilermanufacturer’sliteraturedoesnotstatewhetheritisSEDBUK2009orSEDBUK2005,itshouldbeassumedtobeSEDBUK2005.
10 ReferstotheefficiencymethodologysetoutinDirective2009/125/ECforenergyperformancerelatedproducts.11 Efficiencyisheatoutputdividedbycalorificvalueoffuel.Thenetcalorificvalueofafuelexcludesthelatentheatofwatervapourintheexhaust,andsoislowerthanthegross
calorificvalue.EuropeanstandardsnormallyusenetcalorificvalueswhileSAP2012usesgrossvalues.SAPTableE4givesfactorsforconvertingnetefficiencytogrossefficiency.
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Table 1 Recommended minimum energy efficiency standards for building services (continued)
Panelheaters N/A
Storage,includingintegratedstorage/direct N/A
Solid fuel heating Efficiency (gross) Feed
B1 Simpleopenfire–inset 37% Batch
B2 Openfire–freestandingconvector 47% Batch
B3 Openfireinsetconvector 45%mineralfuels
43%woodfuels
C1/2 Openfireandboiler(insetorfreestanding) 50% Batch
D1/2/3 Openfire+highoutputboiler(trapeziumandrectangulargrates)
63% Batch
D4 Openfire+highoutputboiler(rectangle) 63% Batch
E1 Dryroomheater(drystove) 65% Batch/auto
E2 Dryroomheater–woodlogsonly 65% Batch
E3 Dryroomheater–multi-fuel 65% Batch
E4 Dryroomheater–pelletstove 65%partload
70%nominalload
Auto
F Roomheaterwithboiler 67%mineralfuelsandwoodlogs
70%woodpellets–partload
75%woodpellets–nominalload
Batch/auto
G1 Cookerwithoutboilernotexceeding3.5kW 65%mineralfuels55%woodfuels
Batch
G2 Cookerwithheatingboilerexceeding3.5kW 65%mineralfuels60%woodfuels
Batch
J2 Independentboiler–woodlogsonly 75% Batch
J3 Independentboiler–multi-fuel 65%mineralfuels75%woodlogs
Batch
J4 Independentboiler–anthracite 70%upto20.5kW75%above20.5kW
Auto
J5 Independentboiler–wood/pellets/chips 75%nominalload70%partload
Auto
Slowheatreleaseappliances 65% Batch
One-offtiled/mortaredstoves 70% Batch
Community heating Seasonal efficiency
Boilers SeeNon-Domestic Building Services Compliance Guide
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Table 1 Recommended minimum energy efficiency standards for building services (continued)
Mechanical ventilation Specific fan power (SFP) (W/(l.s))
Intermittentextract 0.5
Continuousextract 0.7
Continuoussupply 0.5
Continuoussupplyandextractwithheatrecovery 1.5
Heat recovery Dry heat recovery efficiency
Balancedmechanicalventilationsystems 70%
Heat pumps – electrically driven Coefficient of performance (COP)
New build12 Existing build
Air-to-air Spaceheating12kW SeasonalCOP‘D’ratingforthemediantemperaturerangeinBSEN1482513
Allothers Spaceheating 2.5atratingconditionsinBSEN1451114
2.2atratingconditionsinBSEN14511
Domestichotwater 2.0atratingconditionsinBSEN14511
Comfort cooling Energy efficiency ratio (EER)
Air-cooledairconditionersworkingincoolingmode 2.4
Water-cooledairconditionersworkingincoolingmode 2.5
Fixedairconditioners ClassCinSchedule3ofthelabellingscheme(TheEnergyInformation(HouseholdAirConditioners)(No2)Regulations,SI2005/1726)
Solar water heating Circulation pump power
50W2%ofpeakthermalpowerofcollector
Fixed lighting Lighting efficacy
Internallightfittings(75%) 45lamplumenspercircuit-watt
Externallighting–automaticpresenceanddaylightcontrol Lampcapacity100lamp-wattsperlightfitting
Externallighting–manualswitchingandautomaticdaylightcontrol 45lumenspercircuit-watt
Micro-CHP Heating plant emission rate (HPER)
SeeSection13.3a
Heating system circulators Energy Efficiency Index
GlandlessstandaloneGlandless,standaloneandintegrated
0.27until31July20150.23from1August2015
12 SAP2012calculationsusetheheatpumpseasonalperformancefactor(SPF)–eithermeasuredvaluesforproductslistedintheProductCharacteristicsDatabase,orthedefaultvaluesinTable4aforproductsnotlisted.
13 Seasonalcoefficientofperformance(SCOP)isthecurrentEcodesignDirectivemeasureforspaceheatingair-to-airheatpumpswithanoutputofupto12kW.Eventually,themeasureusedwillbetheseasonalprimaryenergyefficiencyratio(SPEER),withtestingandratingtoBSEN14825:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Testing and rating at part load conditions and calculation of seasonal performance.EnergylabellingwiththeSPEERratingwillbemandatoryfrom2015.
14 RatingconditionsarestandardisedconditionsfordeterminingperformancespecifiedinBSEN14511:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling.
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Section 2: Gas-fired space and water heating
2.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofgas-firedspaceheatingandhotwatersystems15indwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Theguidanceappliestosystemsfuelledbynaturalgasandliquidpetroleumgas(LPG)andcovers:
• wetcentralheatingsystems
• rangecookerswithintegralcentralheatingboilers
• warmairheatingsystems
• fixedindependentspaceheatingdevices.
2.2 Key termsFluegasheatrecoverymeansadevicewhichpre-heatsthedomestichotwatersupplybyrecoveringheatfromtheboiler’sflueemissions.
Weathercompensationmeansacontrolfunctionwhichmaintainsinternaltemperaturesbyvaryingtheflowtemperaturefromtheheatgeneratorrelativetothemeasuredoutsideairtemperature.
Loadcompensationmeansacontrolfunctionwhichmaintainsinternaltemperaturesbyvaryingtheflowtemperaturefromtheheatgeneratorrelativetothemeasuredresponseoftheheatingsystem.
Automationmeansacontrolfunctionwhichautomaticallyadjuststimeandtemperaturesettingsbasedonoccupancydetectionand/orstoreddatafromuseradjustmentsovertime.
Optimisationmeansacontrolfunctionwhichstartstheboileroperationattheoptimumtimetoachievethesetpointtemperatureatthestartoftheoccupancyperiod.
2.3 Gas-fired wet central heating systemsNew systems
Newsystemsforgas-firedwetcentralheatinginnewandexistingdwellingsshouldmeettheminimumstandardsfor:
a. boilerefficiency,systemcirculation,hotwaterstorage,systempreparationandcommissioninginTable2
b. boilerinterlock,zoning,andtimeandtemperaturecontroloftheheatingandhotwatercircuitsinTable3
c. pipeworkinsulationinTable5.
Work in existing buildings
Componentsinstalledasreplacementsinexistingsystemsshouldmeetthesamestandardsasfornewsystems,exceptwhereindicatedotherwiseinTable4.
Whereaneworreplacementgas-firedboilerisinstalledinanexistingdwelling,bothofthefollowingminimumstandardsshouldbemet:
a. boilerefficiency,inTable2
15 AllgasappliancesmustbeinstalledbyacompetentpersoninaccordancewiththecurrentissueoftheGasSafety(InstallationandUse)Regulations.Theinstallationshouldfollowthemanufacturer’sinstructionsandshouldcomplywithallrelevantpartsoftheBuildingRegulationsand,forwetsystems,theWaterRegulations.
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Table 2 Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for gas-fired wet central heating systems
Minimum standard Supplementary information
1.0 Efficiency
a. TheboilerSEDBUK2009efficiencyforboilersinnewdwellingsshouldnotbelessthan88%.
b. TheboilerErPefficiencyforboilersinstalledinexistingdwellingsshouldnotbelessthan92%.
c. Inexistingdwellings,intheexceptionalcircumstancesdefinedintheDCLGGuide to the condensing boiler installation assessment procedure for dwellings16,theErPefficiencystandardwouldnotapplyandinsteadtheboilerSEDBUK2009efficiencyshouldnotbelessthan78%ifnaturalgas-fired,ornotlessthan80%ifLPG-fired.
d. TheboilerefficiencyforheatingboilersthatarecombinedwithrangecookersshouldbeasdefinedinSection2.3.
TheSAPProductCharacteristicsDatabase(PCDB)atwww.ncm-pcdb.org.uk/sapdisplaysseparateSAPwinterandsummerseasonalefficienciesforboilersheldwithinit.SAP2012(availableatwww.bre.co.uk/sap2012)usesthesevaluestocalculatethecarbondioxideemissionrateforadwelling.SAPwinterandsummerseasonalefficienciesarederivedfromSEDBUK2009values.
SEDBUK2009andSEDBUK2005efficiencyvaluesaredifferenttooneanother,andbotharedifferenttotheErPefficiency.IftheSEDBUKefficiencyinaboilermanufacturer’sliteraturedoesnotstatewhetheritisSEDBUK2009orSEDBUK2005,itshouldbeassumedtobeSEDBUK2005.MinimumSEDBUK2005efficiencyvaluesforboilersaresetoutinTable1andinthe2010editionofthisguide
AllboilermanufacturersshouldbecalculatinganddeclaringtheenergyefficiencyofboilersinlinewiththeERPmethodology.Forboilersinstalledinexistingbuildings,theErPefficiencyshouldbeusedandnottheSEDBUKefficiencyvalues.TheDCLGGuide to the condensing boiler installation assessment procedure for dwellingssetsouttheapprovedprocedureforestablishingtheexceptionalcircumstancesinwhichboilersmaybeofthenon-condensingtype.
Systemswithcondensingboilersshouldbedesignedtohavelowprimaryreturnwatertemperatures,preferablylessthan55°C,tomaximisecondensingoperation.Lowreturnwatertemperaturescanbeobtainedthroughtechniquessuchasweathercompensationandtheuseoflowtemperatureheatemitters(forexamplecorrectly-sizedradiatorsandunderfloorheatingelements).
Lowtemperatureheatemitterswillalsobecompatiblewithlowtemperatureheatgenerators,suchasheatpumps,thatmightbeinstalledasreplacementsinthefuture.
b. boilerinterlock,timeandtemperaturecontrol.
Iftheneworreplacementgas-firedboilerisacombinationboiler,thefollowingstandardshouldalsobemet:
c. atleastoneoftheenergyefficiencymeasuresinthe‘Minimumstandard’columnofTable4,section2.0.
Table4listsminimumstandardswhenreplacingcomponentsofgas-firedwetcentralheatingsystems.Table4inadditionidentifiesgoodpracticeupgradestotherestofthesystem(beyondtherequirementsoftheBuildingRegulations)whenmakingplannedandemergencyreplacements.
16 Guide to the condensing boiler installation assessment procedure for dwellings,ODPM,2005.
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Table 2 Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for gas-fired wet central heating systems (continued)
Minimum standard Supplementary information
2.0 System circulation
a. Spaceheatingsystemsanddomestichotwaterprimarycircuitsshouldhavefullypumpedcirculation.
b. Iftheboilermanufacturer’sinstructionsadviseinstallationofabypass,anautomaticbypassvalveshouldbeprovidedandthemanufacturer’sinstructionsonminimumpipelengthfollowed.
3.0 Hot water storage
a. VentedcopperhotwaterstoragecylindersshouldcomplywiththeheatlossandheatexchangerrequirementsofBS1566:2002Part1.
b. CopperhotwaterstoragecombinationunitsshouldcomplywithBS3198:1981.
c. PrimarystoragesystemsshouldmeettheinsulationrequirementsoftheHotWaterAssociationPerformance specification for thermal stores.
d. UnventedhotwaterstoragesystemproductsshouldcomplywithBSEN12897:2006oranequivalentstandard.
e. Thestandingheatlossforallhotwaterstoragevesselsina.,b.,c.andd.aboveshouldnotexceedQ1.15(0.20.051V2/3)kWh/day,whereVisthevolumeofthecylinderinlitres.
f. Allhotwatervesselsshouldcarryalabelwiththefollowinginformation:
i. typeofvessel(vented,unvented,combinationunitorthermalstore)
ii. nominalcapacityinlitres
iii.standingheatlossinkWh/day
iv.heatexchangerperformanceinkW
v. referencetoproductcompliancewithrelevantstandard(e.g.BS1566,BSEN12897)andlogosofaccreditationbodiesasrequired.
Forlabellingrequirementsforotherheatinputs,seerelevantsections(e.g.Section11forsolar).
IfaventedcylinderisnotmadefromcopperthentheheatlossandheatexchangecharacteristicsshouldbetestedinaccordancewithBSEN12897:2006.
TheHWAthermalstoragespecificationisavailableforfreedownloadfromwww.hotwater.org.uk.
British Standards
BS1566-1:2002Copper indirect cylinders for domestic purposes. Open vented copper cylinders. Requirements and test methods.
BSEN12897:2006Water supply. Specification for indirectly heated unvented (closed) storage water heaters.
BS3198:1981Copper hot water storage combination units for domestic purposes.
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Table 2 Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for gas-fired wet central heating systems (continued)
Minimum standard Supplementary information
4.0 System preparation and water treatment
a. Centralheatingsystemsshouldbethoroughlycleanedandflushedoutbeforeinstallinganewboiler.
b. Duringfinalfillingofthesystem,achemicalwatertreatmentinhibitormeetingthemanufacturer’sspecificationorotherappropriatestandardshouldbeaddedtotheprimarycircuittocontrolcorrosionandtheformationofscaleandsludge.
c. Installersshouldalsorefertotheboilermanufacturer’sinstallationinstructionsforappropriatetreatmentproductsandspecialrequirementsforindividualboilermodels.
d. Wherethemainstotalwaterhardnessexceeds200partspermillion,provisionshouldbemadetotreatthefeedwatertowaterheatersandthehotwatercircuitofcombinationboilerstoreducetherateofaccumulationoflimescale.
e. Forsolarthermalsystems,seeSection11.
InhibitorsshouldbeBuildCertapprovedorequivalent.
Limescalecanbecontrolledbytheuseofchemicallimescaleinhibitors,combinedcorrosionandlimescaleinhibitors,polyphosphatedosing,electrolyticscalereducersorwatersofteners.TherelevantstandardforwatertreatmentisBS7593:2006Code of practice for treatment of water in domestic hot water central heating systems.BS7593notesthat“naturallysoftwatersoflowalkalinityorthosesuppliedviaabase-exchangeresinsoftenerhaveanincreasedpotentialforcorrosion,and,iftheyareusedinanycentralheatingsystem,acorrosioninhibitorspecificallyformulatedforthepurposeshouldbeaddedandproperlymaintained.”Manufacturersshouldbeconsultedforadvice,payingparticularattentiontodosagelevels.
Specialradiatorvalvesareavailablethatwillsealofftheradiatoraswellastheheatingcircuittopreventlossofinhibitorwhenremovingaradiatorforserviceormaintenance.
Afiltercanalsobefittedtothecentralheatingcircuittohelpmaintaintheefficiencyandreliabilityofthesystem.
5.0 Commiss-ioning
a. Oncompletionoftheinstallationofaboilerorhotwaterstoragesystemandassociatedequipmentsuchaspipework,pumpsandcontrols,theequipmentshouldbecommissionedinaccordancewiththemanufacturer’sinstructions.Theseinstructionswillbespecifictotheparticularboilerorhotwaterstoragesystem.
b. Theinstallershouldexplainfullytotheuserhowtooperatethesysteminanenergyefficientmanner,andleavebehindanyusermanualsprovidedbymanufacturers.
The Benchmark System
TheBenchmarkCommissioningChecklistcanbeusedtoshowthatcommissioninghasbeencarriedoutsatisfactorily.Benchmarklicence-holdersprovideachecklistwiththeapplianceforcompletionbythepersonscommissioningthesystemsothattheycanrecordthatallthecheckshavebeenmadeandtheresultsshowefficientoperationoftheequipmentincompliancewiththeBuildingRegulations.TheBenchmarkchecklistshouldbeprovidedtothebuilder,orthehouseholderinthecaseofworkinexistingdwellings,anappointedagent,ortheenduser.ABenchmarkCommissioningChecklistwillbeincludedinallHHICgasboilermanufacturermembers’installationmanualstohelpinstallersrecordinformationabouttheinstallationinordertoassistwithservicingandrepairs.Forexample,detailsofsystemcleanersandinhibitorscanberecorded.OnlymanufacturingcompanieswhoholdaBenchmarklicencewillbeeligibletousetheBenchmarklogoandtheapprovedlogbookwordingandlayout.(BenchmarkisregisteredasaEuropeanCollectiveMarkbytheHeatingandHotWaterIndustryCouncil,andthecontentiscopyright.)
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Table 3 Recommended minimum controls for new gas-fired wet central heating systems[1][2]
Control type Minimum standard
1.0 Boiler interlock
a. Systemcontrolsshouldbewiredsothatwhenthereisnodemandforspaceheatingorhotwater,theboilerandpumpareswitchedoff.
2.0Zoning
a. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzones,eachwithanindependentlycontrolledheatingcircuit[3].
b. Dwellingswithatotalfloorarea[4]150m2mayhaveasinglespaceheatingzone[5].
3.0Control of space heating
a. Eachspaceheatingcircuitshouldbeprovidedwith:
i. independenttimecontrol,andeither:
ii. aroomthermostatorprogrammableroomthermostatlocatedinareferenceroom[6]servedbytheheatingcircuit,togetherwithindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs)onallradiatorsoutsidethereferencerooms,or
iii.individualnetworkedradiatorcontrolsineachroomonthecircuit.
4.0Control of hot water
a. Domestichotwatercircuitssuppliedfromahotwaterstore(i.e.notproducedinstantaneouslyasbyacombinationboiler)shouldbeprovidedwith:
i. independenttimecontrol,and
ii. electrictemperaturecontrolusing,forexample,acylinderthermostatandazonevalveorthree-portvalve.(Iftheuseofazonevalveisnotappropriate,aswiththermalstores,asecondpumpcouldbesubstitutedforthezonevalve.)
Notes[1] Thestandardsinthistableapplytonewgas-firedwetcentralheatingsystems.Inexistingdwellings,thestandardsset
outinTable4willapplyinaddition.[2] Alwaysalsofollowmanufacturers’instructions.[3] Aheatingcircuitreferstoapipeworkrunservinganumberofradiatorsthatiscontrolledbyitsownzonevalve.[4] Therelevantfloorareaistheareawithintheinsulatedenvelopeofthedwelling,includinginternalcupboardsand
stairwells.[5] TheSAPnotionaldwellingassumesatleasttwospaceheatingzonesforallfloorareas,unlessthedwellingissingle
storey,openplanwithalivingarea70%ofthetotalfloorarea.[6] Areferenceroomisaroomthatwillactasthemaintemperaturecontrolforthewholecircuitandwherenoother
formofsystemtemperaturecontrolispresent.
Table 4 Recommended minimum standards when replacing components of gas-fired wet central heating systems[1]
Component Reason Minimum standard Good practice[2]
1.0Hot water cylinder
Emergency a. Forcopperventedcylindersandcombinationunits,thestandinglossesshouldnotexceedQ1.28(0.20.051V2/3)kWh/day,whereVisthevolumeofthecylinderinlitres.
b. Installanelectrictemperaturecontrol,suchasacylinderthermostat.Wherethecylinderorinstallationisofatypethatprecludesthefittingofwiredcontrols,installeitherawirelessorthermo-mechanicalhotwatercylinderthermostatorelectrictemperaturecontrol.
c. Ifseparatetimecontrolfortheheatingcircuitisnotpresent,useofsingletimecontrolforspaceheatingandhotwaterisacceptable.
a. Upgradegravity-fedsystemstofullypumped.
b. Installaboilerinterlockandseparatetimingforspaceheatingandhotwater.
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Table 4 Recommended minimum standards when replacing components of gas-fired wet central heating systems (continued) [1]
Component Reason Minimum standard Good practice[2]
Planned d. Installaboilerinterlockandseparatetimingforspaceheatingandhotwater.
c. Upgradegravity-fedsystemstofullypumped.
2.0Boiler
Emergency/planned
All boiler types except heating boilers that are combined with range cookersa. TheErP[3]seasonalefficiencyoftheboilershould
beaminimumof92%andnotsignificantlylessthantheefficiencyoftheappliancebeingreplaced–assetoutinparagraph1.8.
b. IntheexceptionalcircumstancesdefinedintheGuide to the condensing boiler installation assessment procedure for dwellings[4],theboilerSEDBUK2009efficiencyshouldnotbelessthan78%ifnaturalgas-fired,ornotlessthan80%ifLPG-fired.Inthesecircumstancestheadditionalrequirementsforcombinationboilerswouldnotapply.
c. Installaboilerinterlockasdefinedfornewsystems.
d. Timeandtemperaturecontrolshouldbeinstalledfortheheatingsystem.
Combination boilerse. Inadditiontotheabove,atleastoneofthe
followingenergyefficiencymeasuresshouldbeinstalled.Themeasure(s)chosenshouldbeappropriatetothesysteminwhichitisinstalled:
i. Fluegasheatrecovery.
ii. Weathercompensation.
iii.Loadcompensation.
iv.Smartthermostatwithautomationandoptimisation.
a. Upgradegravity-fedsystemstofullypumped.
b. Fitindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs)onallradiatorsexceptthoseinthereferenceroom.
3.0Radiator
Emergency a. FitaTRVtothereplacementradiatorifinaroomwithoutaroomthermostat.
Planned b. FitTRVstoallradiatorsinroomswithoutaroomthermostat.
4.0New heating system – existing pipework retained
Planned a. Thenewboileranditscontrolsshouldmeetthestandardsinsection2.0ofthistable.
b. FitindividualradiatorcontrolssuchasTRVsonallradiatorsexceptthoseinthereferenceroom.
a. Indwellingswithatotalfloorarea150m2,installatleasttwoheatingcircuits,eachwithindependenttimeandtemperaturecontrol,togetherwithindividualradiatorcontrolssuchasTRVsonallradiatorsexceptthoseinthereferencerooms.
Notes[1] Alwaysalsofollowmanufacturers’instructions.[2] Bestpracticewouldbeasforanewsystem.[3] ReferstotheefficiencymethodologysetoutinDirective2009/125/ECforenergyperformancerelatedproducts.[4] Guide to the condensing boiler installation assessment procedure for dwellings,ODPM,2005.
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Table 5 Recommended minimum standards for insulation of pipework in gas-fired wet central heating systems
Minimum standard Supplementary information
a. PipesshouldbeinsulatedtocomplywiththemaximumpermissibleheatlossindicatedintheSupplementaryinformationcolumn,andlabelledaccordingly,asfollows:
i. Primarycirculationpipesforheatingcircuitsshouldbeinsulatedwherevertheypassoutsidetheheatedlivingspaceorthroughvoidswhichcommunicatewithandareventilatedfromunheatedspaces.
ii. Primarycirculationpipesfordomestichotwatercircuitsshouldbeinsulatedthroughouttheirlength,subjectonlytopracticalconstraintsimposedbytheneedtopenetratejoistsandotherstructuralelements.
iii.Allpipesconnectedtohotwaterstoragevessels,includingtheventpipe,shouldbeinsulatedforatleast1metrefromtheirpointsofconnectiontothecylinder(ortheyshouldbeinsulateduptothepointwheretheybecomeconcealed).
iv. Ifsecondarycirculationisused,allpipeskepthotbythatcirculationshouldbeinsulated.
b. Wheneveraboilerorhotwaterstoragevesselisreplacedinanexistingsystem,anypipesthatareexposedaspartoftheworkorareotherwiseaccessibleshouldbeinsulatedasrecommendedabove–ortosomelesserstandardwherepracticalconstraintsdictate.
Pipe outside diameter (mm)8
1012152228354254
Maximum heat loss (W/m)7.067.237.357.899. 1 2
10.0711 .0812. 1 914. 1 2
Inassessingthethicknessofinsulationrequired,standardisedconditionsshouldbeassumedinallcompliancecalculations,basedonahorizontalpipeat60°Cinstillairat15°C.
FurtherguidanceonconvertingheatlosslimitstoinsulationthicknessforspecificthermalconductivitiesisavailableinTIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
Insulation of pipework in unheated areasItmaybenecessarytoprotectcentralheatingandhotwaterpipeworkinunheatedareasagainstfreezing.Guidanceisavailablein:
• BS5422:2009 Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range -40°C to +700°C.
• BREReportNo262 Thermal insulation: avoiding risks, 2002edition.
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2.4 Gas-fired range cookers with integral central heating boilerNote:Thissectiondoesnotapplytoapplianceswithfullyindependentboilerandcookerpartswithinasharedcase.Forthese,thestandardsfortheboilerareassetoutinSection2.3.
Wheregas-firedrangecookerswithanintegralcentralheatingboiler(withinasingleappliancebody)areprovidedaspartofanewsystemorasareplacementcomponent:
a. Theapplianceshouldhavetwoindependentlycontrolledburners(oneforthecookingfunctionandonefortheboiler).
b. TheSEDBUK2009efficiencyoftheintegralboilershouldnotbelessthan75%.Themanufacturer’sdeclarationofapplianceperformanceandSEDBUKvalueshouldincludethefollowingwords:
i. Seasonal efficiency (SEDBUK) = xx %
ii. Case heat emission value = yy kW
iii. Heat transfer to water at full load = zz kW
iv. The values are used in the UK Government’s Standard Assessment Procedure (SAP) for the energy rating of dwellings. The test data from which the values have been calculated has been certified by {insert name and/or identification of Notified Body}. See: www.rangeefficiency.org.uk.
Iftheintegralboilerisacondensingboiler,thedeclarationshouldmakeclearwhethertheefficiencyhasbeencalculatedinaccordancewithSEDBUK2005orSEDBUK2009.Ifitdoesnot,thenSEDBUK2005mustbeassumed.
c. Theintegralboilershouldmeettheminimumstandardsforsystemcirculation,hotwaterstorage,systempreparation,commissioning,controlsandinsulationinTables2,3and5(gas-firedcentralheatingsystems).
2.5 Gas-fired warm air heatingNewsystemsandreplacementcomponentsforgas-firedwarmairheatingshouldmeettheminimumstandardsfor:
a. efficiencyandinstallationinTable6
b. zoning,timecontrolandtemperaturecontrolfor(a)spaceheatingwithouthotwaterand(b)spaceheatingcombinedwithwaterheatinginTable7.
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Table 6 Recommended minimum standards for efficiency and installation of gas-fired warm air heating systems
Minimum standard Supplementary information
1.0 Efficiency
a. Gas-firedwarmairunitsshouldmeettherequirements,asappropriatetothedesignoftheappliance,of:
i. BSEN778:2009,or
ii. BSEN1319:2009.
b. Ifagas-firedcirculatorisincorporatedinthewarmairunittoprovidedomestichotwater,itshouldbeabletodeliverfullandpartloadefficiencyatleastequaltothatprescribedbyBSEN483:1999+A4:2007.
c. Themanufacturer’sdeclarationofapplianceperformanceshouldincludethefollowingwords:
i. Combined warm air unit and circulator This product has been assessed against the test methods set out in BS EN 778:2009/BS EN 1319:2009/BS EN 483* and certified as meeting those minimum requirements by {insert name and/or identification of Notified Body}.
ii. Warm air unit alone This product has been assessed against the test method set out in BS EN 778:2009/ BS EN 1319:2009* and certified as meeting the minimum requirements by {insert name and/or identification ofNotifiedBody}.*Deleteasappropriate
British Standards
BSEN778:2009Domestic gas-fired forced convection air heaters for space heating not exceeding a net heat input of 70 kW, without a fan to assist transportation of combustion air and/or combustion products.
BSEN1319:2009Domestic gas-fired forced convection air heaters for space heating, with fan-assisted burners not exceeding a net heat input of 70 kW.
BSEN483:1999+A4:2007Gas-fired central heating boilers. Type C boilers of nominal heat input not exceeding 70 kW.
2.0 Installation
a. ThesystemshouldbeinstalledinaccordancewithBS5864:2010.
b. DuctworkthatisnewlyinstalledorreplacedshouldbeinsulatedinaccordancewiththerecommendationsofBS5422:2009.
BS5864:2010Installation and maintenance of gas-fired ducted air heaters of rated input not exceeding 70 kW net (second and third family gases). Specification.
BS5422:2009Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range -40°C to +700°C.
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Table 7 Recommended minimum controls for gas-fired warm air heating systems
(a) Without hot water Minimum standard
1.0 Time and temperature control
a. Wherecontrolsareexternaltotheheater,thesystemshouldbeprovidedwithatimeswitch/programmerandroomthermostat,orprogrammableroomthermostat.
b. Wherecontrolsareintegratedintheheater,thesystemshouldbeprovidedwithatimeswitch/programmerandroomtemperaturesensorlinkedtoheaterfiringandfanspeedcontrol.
2.0 Zoning
a. Dwellingswithatotalfloorarea150m2shouldbedividedintoatleasttwospaceheatingzoneswithindependenttemperaturecontrols,oneofwhichisassignedtothelivingarea.
b. Dwellingswithatotalfloorarea150m2shouldbeprovidedwithatleasttwospaceheatingzoneswithindependenttimeandtemperaturecontrols.
(b) With hot water
1.0 System circulation
a. Thereshouldbepumpedprimarycirculationtothehotwatercylinder.
2.0 Time and temperature control
a. Thespaceheatingandhotwatercircuitsshouldbeprovidedwithindependenttimecontrol.
b. Independenttemperaturecontrolofthehotwatercircuitshouldbeimplementedwithacylinderthermostatandatimingdevice,wiredsuchthatwhenthereisnodemandforhotwaterboththepumpandcirculatorareswitchedoff.
3.0 Zoning
a. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttimecontrols,oneofwhichisassignedtothelivingarea.
b. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttimeandtemperaturecontrols.
2.6 Gas-fired fixed independent space heating appliancesFixedindependentspaceheatingappliancesmaybeinstalledasameansofprimaryorsecondaryspaceheating.
Gas-fired fixed independent appliances for primary space heating
Wheregas-firedfixedindependentspaceheatingappliancesinnewandexistingdwellingsareprovidedastheprimaryheatsource:
a. TheapplianceshouldbeoneofthetypesdescribedinTable8.
b. Theefficiencyoftheappliance(grosscalorificvalue)shouldnotbelessthan63%(70%net).
c. Theappliancemanufacturer’sdeclarationofapplianceperformanceshouldincludethefollowingwords:
The efficiency of this appliance has been measured as specified in {insert appropriate entry from Table 8} and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is [x]%. The test data has been certified by {insert name and/or identification of Notified Body}. The gross efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.
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d. Innewdwellings,eachapplianceshouldbecapable,eitherindependentlyorinconjunctionwithroomthermostatsorothersuitabletemperaturesensingdevices,ofcontrollingthetemperaturesindependentlyinareasthathavedifferentheatingneeds(e.g.separatesleepingandlivingareas).Inexistingdwellings,whereverpractical,temperaturecontrolsshouldbeupgradedtothestandardsrequiredfornewdwellings.
Table 8 Acceptable types of natural gas and LPG-fired fixed independent appliance for primary space heating
British Standard designation (appliance type)
BSEN1266:2002Independent gas-fired convection heaters incorporating a fan to assist transportation of combustion air and/or flue gases.
BS7977-1:2009+A1:2013Specification for safety and rational use of energy of domestic gas appliances. Radiant/convectors.
BSEN613:2001Independent gas-fired convection heaters.
BSEN13278:2013Open fronted gas-fired independent space heaters.
Gas-fired fixed independent appliances for secondary space heating
Wheregas-firedfixedindependentspaceheatingappliancesareprovidedasthesecondaryheatsource:
a. Innewdwellings,theapplianceefficiency(grosscalorificvalue)shouldnotbelessthan63%(70%net).
b. Inexistingdwellings,theapplianceefficiency(grosscalorificvalue)shouldnotbelessthan45%(50%net).
c. Theappliancemanufacturer’sdeclarationofapplianceperformanceshouldincludethefollowingwords:
The efficiency of this appliance has been measured as specified in {insert appropriate entry from Table 9} and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is [x]%. The test data has been certified by {insert name and/or identification of Notified Body}. The efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.
Table 9 Acceptable types of natural gas and LPG-fired fixed independent appliance for secondary space heating
BSEN1266:2002Independent gas-fired convection heaters incorporating a fan to assist transportation of combustion air and/or flue gases.
BS7977-1:2009+A1:2013Specification for safety and rational use of energy of domestic gas appliances. Radiant/convectors.
BSEN613:2001Independent gas-fired convection heaters.
BSEN13278:2013Open fronted gas-fired independent space heaters.
FluelessBSEN14829:2007Independent gas-fired flueless space heaters for nominal heat input not exceeding 6 kW.
Thermalefficiencyrequirementsforthistypeofappliancearenotspecifiedasalltheheatproducedbythecombustionprocessisreleasedintothespacetobeheated.InSAP2012theefficiencyoftheseappliancesisclassedas90%andanadjustmentismadeforventilationinthespaceheatingrequirementcalculation.
BSEN449:2002+A1:2007Specification for dedicated liquefied petroleum gas appliances. Domestic flueless space heaters (including diffusive catalytic combustion heaters).
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2.7 Gas-fired fixed decorative fuel-effect firesThistypeofapplianceisintendedfordecorativepurposesandthereforeaminimumthermalefficiencyisnotspecified.NotethatforthepurposesofSAP2012theefficiencyofdecorativefuel-effectfiresisclassedas20%inthespaceheatingrequirementcalculation.SeeTable4aofSAP2012.
Gas-fireddecorativefiresinnewandexistingdwellingsshould:
a. meettheproductstandardsinBSEN509:2000Decorative fuel-effect gas appliances
b. numbernotmorethanoneapplianceper100m2ofdwellingfloorarea.
2.8 Gas fires for secondary space heating provided as part of a combined fire and back boiler unitWheregasfiresareprovidedasasecondaryheatsourceaspartofacombinedfireandbackboilerunitinanexistingsystem:
a. TheapplianceshouldbeoneofthetypesdescribedinTable10.
b. Theefficiency(grosscalorificvalue)oftheapplianceshouldnotbelessthanthevalueinTable10forthattypeofappliance.
c. Theappliancemanufacturer’sdeclarationofapplianceperformanceshouldincludethefollowingwords:
The efficiency of this appliance has been measured as specified in {insert appropriate entry from Table 10} and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is [x]%. The test data from which it has been calculated has been certified by {insert name and/or identification of Notified Body}. The efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.
Table 10 Minimum appliance efficiencies for gas fires in a combined fire and back boiler unit
British Standard designation (appliance type)
Minimum efficiency % (gross calorific value)
Natural gas LPG
Inset live fuel-effectBS7977-2:2003Specification for safety and rational use of energy of domestic gas appliances. Combined appliances. Gas fire/back boiler.
45 46
All types except inset live fuel-effectBS7977-2:2003Specification for safety and rational use of energy of domestic gas appliances. Combined appliances. Gas fire/back boiler.
63 64
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Supplementary information
Energy Efficiency Best Practice in Housing
CE30Domestic heating by gas: boiler systems.
CE51Central heating system specifications (CHeSS).
CE54Whole house boiler sizing method for houses and flats.
SBGI publications on gas boilers and gas fires
Seewww.sbgi.org.uk.
CORGI Domestic Manual Series
GID1Essential gas safety.
GID2Gas cookers and ranges.
GID3Gas fires and space heaters.
GID5Water heaters.
GID7Central heating wet and dry.
CORGI Design Guides
WCH1Wet central heating system design guide.
WAH1Warm air heating system design guide.
British Standards
BS5440-1:2008Flueing and ventilation for gas appliances of rated input not exceeding 70 kW net (1st, 2nd and 3rd family gases). Specification for installation of gas appliances to chimneys and for maintenance of chimneys.
BS5440-2:2009Flueing and ventilation for gas appliances of rated input not exceeding 70 kW net (1st, 2nd and 3rd family gases). Specification for the installation and maintenance of ventilation provision for gas appliances.
BSEN12828:2012Heating systems in buildings. Design for water-based heating systems.
BSEN12831:2003Heating systems in buildings. Method for calculation of the design heat load.
BSEN14336:2004Heating systems in buildings. Installation and commissioning of water-based heating systems.
BS6798:2009Specification for installation and maintenance of gas-fired boilers of rated input not exceeding 70 kW net.
BS5871-1:2007Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Gas fires, convector heaters, fire/back boilers and heating stoves (2nd and 3rd family gases).
BS5871-2:2005Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Inset live fuel effect gas fires of heat input not exceeding 15 kW, and fire/back boilers (2nd and 3rd family gases).
BS5871-3:2005Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Decorative fuel effect gas appliances of heat input not exceeding 20 kW (2nd and 3rd family gases).
BS5871-4:2007Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Independent gas-fired flueless fires, convector heaters and heating stoves of nominal heat input not exceeding 6 kW (2nd and 3rd family gases).
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Section 3: Oil-fired space and water heating
Section 3: Oil-fired space and water heating
3.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofoil-firedspaceheatingandhotwatersystems17indwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Theguidanceappliestothefollowingtypesofoil-firedheatingsystem:
• wetcentralheatingsystems
• rangecookerswithintegralcentralheatingboilers
• vaporisingappliancesprovidingsecondaryheatingorhotwater
• fixedindependentspaceheatingdevices.
3.2 Oil-fired wet central heating systemsNew systems
Newsystemsforoil-firedcentralheatinginnewandexistingdwellingsshouldmeettheminimumstandardsfor:
a. boilerefficiency,systemcirculation,hotwaterstorage,systempreparationandcommissioninginTable11
b. boilerinterlock,zoning,andtimeandtemperaturecontroloftheheatingandhotwatercircuitsinTable12
c. pipeworkinsulationinTable14.
Work on existing systems
Componentsinstalledasreplacementsinexistingsystemsshouldmeetthesamestandardsasfornewsystems,exceptwhereindicatedotherwiseinTable13.
Table13inadditionidentifiesgoodpracticeupgradestotherestofthesystemwhenmakingplannedandemergencyreplacementsthatgobeyondtherequirementsoftheBuildingRegulations.
17 Alloilappliancesmustbeinstalledbyacompetentperson.Theinstallationshouldfollowthemanufacturer’sinstructionsandshouldcomplywithallrelevantpartsoftheBuildingRegulationsand,forwetsystems,theWaterRegulations.
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Table 11 Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems
Minimum standard Supplementary information
1.0 Efficiency
Regular boilers
a. Theboilershouldbeofthecondensingtype.
b. TheboilerSEDBUK2009efficiencyshouldnotbelessthan88%.
c. Inexistingdwellings,compliancewiththerequirementsforboilerefficiencycanbedemonstratedbyfollowingtheguidanceintheDCLGGuide to the condensing boiler installation assessment procedure for dwellings.TheboilerSEDBUK2009efficiencyshouldnotbelessthan84%.
Combination boilers
d. Theboilershouldbeofthecondensingtype.TheboilerSEDBUK2009efficiencyshouldnotbelessthan86%.
e. Inexistingdwellings,compliancewiththerequirementsforboilerefficiencycanbedemonstratedbyfollowingtheguidanceintheDCLGGuide to the condensing boiler installation assessment procedure for dwellings.TheboilerSEDBUK2009efficiencyshouldnotbelessthan82%.
Range cooker boilers
f. TheboilerefficiencyforheatingboilersthatarecombinedwithrangecookersshouldbeasdefinedinSection3.3Oil-fired cookers with integral central heating boilers.
TheBoilerEfficiencyDatabaseatwww.boilers.org.ukispartoftheSAPProductCharacteristicsDatabase(PCDB)anddisplaysseparateSAPwinterandsummerseasonalefficienciesforboilersheldwithinit.SAP2012(availableatwww.bre.co.uk/sap2012)usesthesevaluestocalculatethecarbondioxideemissionrateforadwelling.SAPwinterandsummerseasonalefficienciesarederivedfromSEDBUK2009values.
SEDBUK2009andSEDBUK2005efficiencyvaluesaredifferent.IftheSEDBUKefficiencyinaboilermanufacturer’sliteraturedoesnotstatewhetheritisSEDBUK2009orSEDBUK2005,itshouldbeassumedtobeSEDBUK2005.MinimumSEDBUK2005efficiencyvaluesforboilersaresetoutinTable1andinthe2010editionofthisguide.
TheDCLGGuide to the condensing boiler installation assessment procedure for dwellingssetsouttheapprovedprocedureforestablishingtheexceptionalcircumstancesinwhichboilersmaybeofthenon-condensingtype.
Systemswithcondensingboilersshouldbedesignedtohavelowprimaryreturnwatertemperatures,preferablylessthan55°C,tomaximisecondensingoperation.Lowreturnwatertemperaturescanbeobtainedthroughtechniquessuchasweathercompensationandtheuseoflowtemperatureheatemitters(forexamplecorrectly-sizedradiatorsandunderfloorheatingelements).
Lowtemperatureheatemitterswillalsobecompatiblewithlowtemperatureheatgenerators,suchasheatpumps,thatmightbeinstalledasreplacementsinthefuture.
2.0 System circulation
a. Spaceheatingsystemsanddomestichotwaterprimarycircuitsshouldhavefullypumpedcirculation.
b. Iftheboilermanufacturer’sinstructionsadviseinstallationofabypass,anautomaticbypassvalveshouldbeprovidedandthemanufacturer’sinstructionsonminimumpipelengthfollowed.
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Table 11 Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems (continued)
Minimum standard Supplementary information
3.0 Hot water storage
a. VentedcopperhotwaterstoragecylindersshouldcomplywiththeheatlossandheatexchangerrequirementsofBS1566-1:2002.
b. CopperhotwaterstoragecombinationunitsshouldcomplywithBS3198:1981.
c. PrimarystoragesystemsshouldmeettheinsulationrequirementsoftheHotWaterAssociationPerformance specification for thermal stores.
d. UnventedhotwaterstoragesystemproductsshouldcomplywithBSEN12897:2006oranequivalentstandard.
e. Thestandingheatlossforallhotwaterstoragevesselsina.,b.,c.andd.aboveshouldnotexceedQ1.15(0.20.051V2/3)kWh/day,whereVisthevolumeofthecylinderinlitres.
f. Allhotwatervesselsshouldcarryalabelwiththefollowinginformation:
i. typeofvessel(vented,unvented,combinationunitorthermalstore)
ii. nominalcapacityinlitres
iii.standingheatlossinkWh/day
iv. heatexchangerperformanceinkW
v. referencetoproductcompliancewithrelevantstandard(e.g.BS1566-1,BSEN12897)andlogosofaccreditationbodiesasrequired.
Forlabellingrequirementsforotherheatinputs,seerelevantsections(e.g.Section11forsolar).
IfaventedcylinderisnotmadefromcopperthentheheatlossandheatexchangecharacteristicsshouldbetestedinaccordancewithBSEN12897:2006.
TheHWAthermalstoragespecificationisavailablefromwww.hotwater.org.uk.
British Standards
BS1566-1:2002Copper indirect cylinders for domestic purposes. Open vented copper cylinders. Requirements and test methods.
BSEN12897:2006Water supply. Specification for indirectly heated unvented (closed) storage water heaters.
BS3198:1981Copper hot water storage combination units for domestic purposes.
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Table 11 Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems (continued)
Minimum standard Supplementary information
4.0 System preparation and water treatment
a. Centralheatingsystemsshouldbethoroughlycleanedandflushedoutbeforeinstallinganewboiler.
b. Duringfinalfillingofthesystem,achemicalwatertreatmentinhibitormeetingthemanufacturer’sspecificationorotherappropriatestandardshouldbeaddedtotheprimarycircuittocontrolcorrosionandtheformationofscaleandsludge.
c. Installersshouldalsorefertotheboilermanufacturer’sinstallationinstructionsforappropriatetreatmentproductsandspecialrequirementsforindividualboilermodels.
d. Wherethemainstotalwaterhardnessexceeds200partspermillion,provisionshouldbemadetotreatthefeedwatertowaterheatersandthehotwatercircuitofcombinationboilerstoreducetherateofaccumulationoflimescale.
e. Forsolarthermalsystems,seeSection11.
InhibitorsshouldbeBuildCertapprovedorequivalent.
Limescalecanbecontrolledbytheuseofchemicallimescaleinhibitors,combinedcorrosionandlimescaleinhibitors,polyphosphatedosing,electrolyticscalereducersorwatersofteners.TherelevantstandardforwatertreatmentisBS7593:2006Code of practice for treatment of water in domestic hot water central heating systems.BS7593notesthat“naturallysoftwatersoflowalkalinityorthosesuppliedviaabase-exchangeresinsoftenerhaveanincreasedpotentialforcorrosion,and,iftheyareusedinanycentralheatingsystem,acorrosioninhibitorspecificallyformulatedforthepurposeshouldbeaddedandproperlymaintained.”Manufacturersshouldbeconsultedforadvice,payingparticularattentiontodosagelevels.
Specialradiatorvalvesareavailablethatwillsealofftheradiatoraswellastheheatingcircuittopreventlossofinhibitorwhenremovingaradiatorforserviceormaintenance.
Afiltercanalsobefittedtothecentralheatingcircuittohelpmaintaintheefficiencyandreliabilityofthesystem.
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Table 11 Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems (continued)
Minimum standard Supplementary information
5.0 Commissioning
a. Oncompletionoftheinstallationofaboilerorahotwaterstoragesystem,togetherwithassociatedequipmentsuchaspipework,pumpsandcontrols,theequipmentshouldbecommissionedinaccordancewiththemanufacturer’sinstructions.Theseinstructionswillbespecifictotheparticularboilerorhotwaterstoragesystem.
b. Theinstallershouldexplainfullytotheuserhowtooperatethesysteminanenergyefficientmanner,andleavebehindanyusermanualsprovidedbymanufacturers.
TheOil Controlled Document System(asproducedandmanagedbyOFTEC)canbeusedtoshowthatoil-firedappliancesandrelatedsystemshavebeeninstalledandcommissionedsatisfactorilybylistingandrecordingworksandcheckswhicharedeemednecessaryfortheefficientoperationoftheapplianceandsystemincompliancewiththeBuildingRegulations.Acopyofeachcompletedformisleftwiththehouseholderoragentforrecordand/orBuildingControlinspectionpurposes,andacopyisretainedbytheissuinginstallerandengineer.
OFTECbrandedformsareprovidedfortheuseofOFTECRegisteredCompetentPersonsandnon-OFTECbrandedformsareavailableforotherscarryingoutoil-firedinstallationandcommissioningworks.ToassistinstallersOFTECoilappliancemanufacturingmembersmayprovideformsCD/10andCD/11withtheirequipment.
Controlled Document CD/10
InstallingengineersshouldcompleteOFTECFormCD/10toshowthattheyhavecompletedtheinstallationofanoil-firedapplianceandcontrolsandwetsystemcommissioningpriortofinalappliancecommissioning.
Controlled Document CD/11
Commissioningengineersofoil-firedappliancesshouldcompleteOFTECFormCD/11torecordandshowthattheyhavecompletedthecommissioningoftheapplianceandthattheyhaveleftitoperatinginasafeandefficientmanner.
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Table 12 Recommended minimum controls for oil-fired wet central heating systems[1]
Control type Minimum standard
1.0 Boiler interlock
a. Systemcontrolsshouldbewiredsothatwhenthereisnodemandforspaceheatingorhotwater,theboilerandpumpareswitchedoff.
2.0Zoning
a. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzones,eachwithanindependentlycontrolledheatingcircuit[2].
b. Dwellingswithatotalfloorarea[3]150m2mayhaveasinglespaceheatingzone[4].
3.0Control of space heating
a. Eachspaceheatingcircuitshouldbeprovidedwith:
i. independenttimecontrol,andeither:
ii. aroomthermostatorprogrammableroomthermostatlocatedinareferenceroom[5]servedbytheheatingcircuit,togetherwithindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs)onallradiatorsoutsidethereferencerooms,or
iii.individualnetworkedradiatorcontrolsineachroomonthecircuit.
4.0Control of hot water
a. Domestichotwatercircuitssuppliedfromahotwaterstore(i.e.notproducedinstantaneouslyasbyacombinationboiler)shouldbeprovidedwith:
i. independenttimecontrol,and
ii. electrictemperaturecontrolusing,forexample,acylinderthermostatandazonevalveorthree-portvalve.(Iftheuseofazonevalveisnotappropriate,aswiththermalstores,asecondpumpcouldbesubstitutedforthezonevalve.)
Notes[1] Alwaysalsofollowmanufacturers’instructions.[2] Aheatingcircuitreferstoapipeworkrunservinganumberofradiatorsthatiscontrolledbyitsownzonevalve.[3] Therelevantfloorareaistheareawithintheinsulatedenvelopeofthedwelling,includinginternalcupboardsand
stairwells.[4] TheSAPnotionaldwellingassumesatleasttwospaceheatingzonesforallfloorareas,unlessthedwellingissingle
storey,openplanwithalivingarea70%ofthetotalfloorarea.[5] Areferenceroomisaroomthatwillactasthemaintemperaturecontrolforthewholecircuitandwherenoother
formofsystemtemperaturecontrolispresent.
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Table 13 Recommended minimum standards when replacing components of oil-fired wet central heating systems[1]
Component Reason Minimum standard Good practice[2]
1.0Hot water cylinder
Emergency a. Forcopperventedcylindersandcombinationunits,thestandinglossesshouldnotexceedQ1.28(0.20.051V2/3)kWh/day,whereVisthevolumeofthecylinderinlitres.
b. Installanelectrictemperaturecontrol,suchasacylinderthermostat.Wherethecylinderorinstallationisofatypethatprecludesthefittingofwiredcontrols,installeitherawirelessorthermo-mechanicalhotwatercylinderthermostatorelectrictemperaturecontrol.
c. Ifseparatetimecontrolfortheheatingcircuitisnotpresent,useofsingletimecontrolforspaceheatingandhotwaterisacceptable.
a. Upgradegravity-fedsystemstofullypumped.
b. Installaboilerinterlockandseparatetimingforspaceheatingandhotwater.
Planned d. Installaboilerinterlockandseparatetimingforspaceheatingandhotwater.
c. Upgradegravity-fedsystemstofullypumped.
2.0Boiler
Emergency/planned
a. TheefficiencyofthenewapplianceshouldbeasspecifiedfornewsystemsinTable11andnotsignificantlylessthantheefficiencyoftheappliancebeingreplaced–assetoutinparagraph1.8.
b. Installaboilerinterlockasdefinedfornewsystems.
c. Timeandtemperaturecontrolshouldbeinstalledfortheheatingsystem.
a. Upgradegravity-fedsystemstofullypumped.
b. Fitindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs)onallradiatorsexceptthoseinthereferenceroom.
3.0Radiator
Emergency a. FitaTRVtothereplacementradiatorifinaroomwithoutaroomthermostat.
Planned b. FitTRVstoallradiatorsinroomswithoutaroomthermostat.
4.0New heating system – existing pipework retained
Planned a. Installaboilerinterlockasdefinedfornewsystems.
b. FitindividualradiatorcontrolssuchasTRVsonallradiatorsexceptthoseinthereferenceroom.
a. Indwellingswithatotalfloorarea150m2,installatleasttwoheatingcircuits,eachwithindependenttimeandtemperaturecontrol,togetherwithindividualradiatorcontrolssuchasTRVsonallradiatorsexceptthoseinthereferencerooms.
Notes[1] Alwaysalsofollowmanufacturers’instructions.[2] Bestpracticewouldbeasforanewsystem.
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Table 14 Recommended minimum standards for insulation of pipework in oil-fired wet central heating systems
Minimum standard Supplementary information
a. PipesshouldbeinsulatedtocomplywiththemaximumpermissibleheatlossindicatedintheSupplementaryinformationcolumn,andlabelledaccordingly,asfollows:
i. Primarycirculationpipesforheatingcircuitsshouldbeinsulatedwherevertheypassoutsidetheheatedlivingspaceorthroughvoidswhichcommunicatewithandareventilatedfromunheatedspaces.
ii. Primarycirculationpipesfordomestichotwatercircuitsshouldbeinsulatedthroughouttheirlength,subjectonlytopracticalconstraintsimposedbytheneedtopenetratejoistsandotherstructuralelements.
iii.Allpipesconnectedtohotwaterstoragevessels,includingtheventpipe,shouldbeinsulatedforatleast1metrefromtheirpointsofconnectiontothecylinder(ortheyshouldbeinsulateduptothepointwheretheybecomeconcealed).
iv. Ifsecondarycirculationisused,allpipeskepthotbythatcirculationshouldbeinsulated.
b. Wheneveraboilerorhotwaterstoragevesselisreplacedinanexistingsystem,anypipesthatareexposedaspartoftheworkorareotherwiseaccessibleshouldbeinsulatedasrecommendedabove–ortosomelesserstandardwherepracticalconstraintsdictate.
Pipe outside diameter (mm)8
1012152228354254
Maximum heat loss (W/m)7.067.237.357.899. 1 2
10.0711 .0812. 1 914. 1 2
Inassessingthethicknessofinsulationrequired,standardisedconditionsshouldbeassumedinallcompliancecalculations,basedonahorizontalpipeat60°Cinstillairat15°C.
FurtherguidanceonconvertingheatlosslimitstoinsulationthicknessforspecificthermalconductivitiesisavailableinTIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
Insulation of pipework in unheated areas
Itmaybenecessarytoprotectcentralheatingandhotwaterpipeworkinunheatedareasagainstfreezing.Guidanceisavailablein:
• BS5422:2009 Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range -40°C to +700°C.
• BREReportNo262 Thermal insulation: avoiding risks, 2002edition.
3.3 Oil-fired range cookers with integral central heating boilersThissectionprovidesguidanceonthespecificationofoil-firedrangecookerswithintegralcentralheatingboilersforspaceheatingandhotwaterindwellings.
Note:Theguidanceappliesonlytotwin-burnercookerboilers,whichshouldnotbeconfusedwiththetypeofrangecookerdescribedasasingleburner‘dryheat’rangecooker.Thelatterisintendedonlytoprovideacookingfunction,isnotincludedinSAP2012calculations,anddoesnotcomewithinthescopeoftheBuildingRegulationsenergyefficiencyrequirements.
Whereoil-firedrangecookerswithanintegralcentralheatingboilerareprovidedaspartofnewsystemsorasreplacementcomponentsinexistingsystems:
a. Theapplianceshouldhavetwoindependentlycontrolledburners(oneforthecookingfunctionandonefortheboiler).
b. TheSEDBUK2009efficiencyoftheintegralboilershouldnotbelessthan80%.
c. Themanufacturer’sdeclarationofapplianceperformanceandSEDBUKvalueshouldincludethefollowingwords:
i. Seasonal efficiency (SEDBUK) = xx%
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ii. Case heat emission value = yy kW
iii. Heat transfer to water at full load = zz kW
iv. The efficiency values may be used in the UK Government’s Standard Assessment Procedure (SAP) for the energy rating of dwellings. The test data from which they have been calculated has been certified by {insert name and/or identification of Notified Body}.
Iftheintegralboilerisacondensingboiler,thedeclarationshouldmakeclearwhethertheefficiencyhasbeencalculatedinaccordancewithSEDBUK2005orSEDBUK2009.Ifitdoesnot,thenSEDBUK2005mustbeassumed.Seewww.rangeefficiency.org.uk.
d. Theintegralboilershouldmeettheminimumstandardsforoil-firedcentralheatingsystemsinTables11,12and14forsystemcirculation,hotwaterstorage,systempreparation,commissioning,controlsandinsulation.
3.4 Continuously-burning oil-fired vaporising appliances providing secondary heating or hot waterThissectionprovidesguidanceonthespecificationofoil-firedvaporisingappliancesprovidingsecondaryheatingorhotwaterfordwellings.Theguidancedoesnotapplytoapplianceswhichhavebeenconvertedfromanotherfuel(forexamplefromsolidfueltooil).
Oil-firedvaporisingappliancesprovidedwithnewsystemsorasreplacementcomponentsinexistingsystemsshouldmeettheminimumstandardsforcontrolsinTable15.
Table 15 Recommended minimum controls for continuously burning oil-fired vaporising appliances
Appliance type Minimum standardSupplementary information
a. Manuallyoperatedappliance,e.g.roomheater.
Theintegralmanualcontrolsasprovidedbyappliancemanufacturer.
Informationabouttheuseofcontrolsshouldbeclearlystatedinthemanufacturer’sliterature.
b. Electricallyoperated(modulating)appliance,e.g.roomheater.
Theintegralorremotethermostaticcontrolsasprovided(orspecified)bytheappliancemanufacturer.
Automaticon/offvaporisingappliances
c. Roomheaterproviding(secondary)spaceheating.
Theintegralthermostaticcontrolsasprovidedbytheappliancemanufacturer.
d. Roomheaterprovidingdomestichotwaterand(secondary)spaceheating.
Theintegralorremotethermostaticcontrolsasprovided(orspecified)bytheappliancemanufacturer.
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3.5 Oil-fired fixed independent space heating appliancesThissectionprovidesguidanceonthespecificationofoil-firedfixedindependentappliancesforprimaryorsecondaryspaceheatingindwellings.
Oil-fired fixed independent appliances for primary heating
Whereoil-firedfixedindependentspaceheatingappliancesareprovidedastheprimaryheatsourceinnewdwellings:
a. Theefficiencyoftheappliance(grosscalorificvalue)shouldnotbelessthan60%.Theappliancemanufacturer’sdeclarationofapplianceperformanceshouldincludethefollowingwords:
The net efficiency of this appliance has been measured as specified in OFS A102:2004 and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is [x]%. The test data has been certified by {insert name and/or identification of Notified Body}. The efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.
b. Eachapplianceshouldbecapable,eitherindependentlyorinconjunctionwithroomthermostatsorothersuitabletemperaturesensingdevices,ofcontrollingthetemperaturesindependentlyinareasthathavedifferentheatingneeds(e.g.separatesleepingandlivingareas).
Oil-fired fixed independent appliances for secondary heating
Oil-firedfixedindependentspaceheatingappliancesinnewdwellingswhichareprovidedasthesecondaryheatsourceshouldhaveanefficiency(grosscalorificvalue)ofnotlessthan60%.
Supplementary Information
EnergyEfficiencyBestPracticeinHousingpublications:
CE29Domestic heating by oil: boiler systems.
CE51Central heating system specifications (CHeSS).
CE54Whole house boiler sizing method for houses and flats.
OFTECTechnicalBooks2,3,4and5(seewww.oftec.org).
BSEN12828:2012Heating systems in buildings. Design for water-based heating systems.
BS5410-1:1997Code of practice for oil firing installations up to 45 kW output capacity for space heating and hot water supply purposes.
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Section 4: Electric heating
Section 4: Electric heating
ThissectionprovidesguidanceonthespecificationoffixedelectricheatingsystemsfordwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
4.1 Scope of guidanceTheguidancegiveninthissectioncoversthefollowingtypesoffixedelectricheatingsystems:
• electricboilersservingcentralheatingsystems
• electricwarmairsystems
• electricpanelheaters
• electricstoragesystemsincludingintegratedstorage/directsystems.
Portable,plug-inappliancesarenotcoveredbytheBuildingRegulationsorbythisguide.
4.2 Electric boilers serving central heating systemsElectricboilersservingwetcentralheatingprovidedwithnewsystemsorasreplacementcomponentsinexistingsystemsshouldmeettheminimumstandardsfor:
a. systemcirculation,systempreparationandcommissioninginTable16
b. boilerinterlock,zoning,andtimecontrolandtemperaturecontrolofheatingandhotwatercircuitsinTable17
c. hotwaterstoragesystemsinTable18
d. pipeworkinsulationinTable19.
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Table 16 Recommended minimum standards for system circulation, preparation and commissioning for electric wet central heating systems
Minimum standard Supplementary information
1.0 System circulation
a. Systemsforspaceheatinganddomestichotwaterprimarycircuitsinnewdwellingsshouldhavefullypumpedcirculation.
b. Iftheboilermanufacturer’sinstructionsadviseinstallationofabypass,thenanautomaticbypassvalveshouldbeused.
2.0 System preparation and water treatment
a. Centralheatingsystemsshouldbethoroughlycleanedandflushedbeforeinstallinganewboiler.
b. Duringfinalfillingofthesystemachemicalwatertreatmentformulationshouldbeaddedtotheprimarycircuittocontrolcorrosionandtheformationofscaleandsludge.
c. Installersshouldalsorefertotheboilermanufacturer’sinstallationinstructionsforappropriatetreatmentproductsandspecialrequirementsforindividualboilermodels.
d. Wherethemainstotalwaterhardnessexceeds200partspermillion,provisionshouldbemadetotreatthefeedwatertowaterheatersandthehotwatercircuitofcombinationboilerstoreducetherateofaccumulationoflimescale.
InhibitorsshouldbeBuildCertapprovedorequivalent.
Limescalecanbecontrolledbytheuseofchemicallimescaleinhibitors,combinedcorrosionandlimescaleinhibitors,polyphosphatedosing,electrolyticscalereducersorwatersofteners.TherelevantstandardforwatertreatmentisBS7593:2006Code of practice for treatment of water in domestic hot water central heating systems.BS7593notesthat“naturallysoftwatersoflowalkalinityorthosesuppliedviaabase-exchangeresinsoftenerhaveanincreasedpotentialforcorrosion,and,iftheyareusedinanycentralheatingsystem,acorrosioninhibitorspecificallyformulatedforthepurposeshouldbeaddedandproperlymaintained.”Manufacturersshouldbeconsultedforadvice,payingparticularattentiontodosagelevels.
Specialradiatorvalvesareavailablethatwillsealofftheradiatoraswellastheheatingcircuittopreventlossofinhibitorwhenremovingaradiatorforserviceormaintenance.
Afiltercanalsobefittedtothecentralheatingcircuittohelpmaintaintheefficiencyandreliabilityofthesystem.
3.0 Commissioning
a. Manufacturers’instructionsforcommissioningshouldbefollowedandacommissioningrecordshouldbecompletedtoshowcompliance.
b. Theinstallershouldexplainfullytotheuserhowtooperatethesysteminanenergyefficientmanner,andleavebehindanyusermanualsprovidedbymanufacturers.
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Table 17 Recommended minimum controls for electric wet central heating systems[1]
Control type Minimum standard
1.0 Boiler temperature control
a. Theboilershouldbefittedwithaflowtemperaturecontrolandbecapableofmodulatingthepowerinputtotheprimarywaterdependingonspaceheatingconditions.
2.0 Boiler interlock
a. Iftheboilersuppliesdomestichotwater,systemcontrolsshouldbewiredsothatwhenthereisnodemandforspaceheatingorhotwater,theboilerandpumpareswitchedoff.
3.0 Zoning
a. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzones,eachwithanindependentlycontrolledheatingcircuit[2].
b. Dwellingswithatotalfloorarea[3]150m2mayhaveasinglespaceheatingzone[4].
4.0 Control of space heating
a. Eachspaceheatingcircuitshouldbeprovidedwith:
i. independenttimecontrolandeither:
ii. aroomthermostatorprogrammableroomthermostatlocatedinareferenceroom[5]servedbytheheatingcircuit,togetherwithindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs)onallradiatorsoutsidethereferencerooms,or
iii.individualnetworkedradiatorcontrolsineachroomonthecircuit.
5.0 Control of hot water
a. Domestichotwatercircuitssuppliedfromaboilerandhotwaterstoreshouldbeprovidedwith:
i. independenttimecontrol,and
ii. electrictemperaturecontrolusing,forexample,acylinderthermostatandazonevalveorthree-portvalve.(Iftheuseofazonevalveisnotappropriate,aswiththermalstores,asecondpumpcouldbesubstitutedforthezonevalve.)
Notes[1] Alwaysalsofollowmanufacturers’instructions.[2] Aheatingcircuitreferstoapipeworkrunservinganumberofradiatorsthatiscontrolledbyitsownzonevalve.[3] Therelevantfloorareaistheareawithintheinsulatedenvelopeofthedwelling,includinginternalcupboardsand
stairwells.[4] TheSAPnotionaldwellingassumesatleasttwospaceheatingzonesforallfloorareas,unlessthedwellingissingle
storey,openplanwithalivingarea70%ofthetotalfloorarea.[5] Areferenceroomisaroomthatwillactasthemaintemperaturecontrolforthewholecircuitandwherenoother
formofsystemtemperaturecontrolispresent.
Supplementary information
Moredetailsoncontrolsystemscanbefoundinmanufacturers’literatureandonTheAssociationofControlsManufacturers(TACMA)websiteatwww.heatingcontrols.org.uk.
Controlsmaybeprovidedbyanyboilermanagementcontrolsystemthatmeetsthespecifiedzoning,timingandtemperatureandboilerinterlockcontrolrequirements.
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Table 18 Recommended minimum standards for hot water storage in electric wet central heating systems
Minimum standard
1.0 Vented systems, including cylinders heated primarily by electricity
a. VentedcopperhotwaterstoragevesselsshouldcomplywithBS1566-1:2002orBS3198:1981.
b. VentedcylindersinmaterialsotherthancoppershouldalsobelabelledascomplyingwiththeheatlossrequirementsofBS1566-1:2002.
c. Forventedreplacements,electricallyheatedcombinationunitsshouldbeinsulatedsuchthattheheatlossdoesnotexceedthevalueQ1.28(0.20.051V2/3)kWh/day,whereVisthenominalcylindervolumeinlitres.Thisappliestoelectricallyheatedcombinationunitsaswellasotherelectricallyheatedcylinders.
d. Inventednewsystems,electricallyheatedcombinationunitsshouldbeinsulatedsuchthattheheatlossdoesnotexceedthevalueQ1.15(0.20.051V2/3)kWh/day,whereVisthenominalcylindervolumeinlitres.Thisappliestoelectricallyheatedcombinationunitsaswellasotherelectricallyheatedcylinders.
2.0 Unvented systems, including cylinders heated primarily by electricity
a. ProductsshouldcomplywithBSEN12897:2006oranequivalentstandard.
b. CylindersheatedprimarilybyelectricityshouldbeinsulatedsuchthattheirheatlossdoesnotexceedQ1.15(0.20.051V2/3)kWh/day,whereVisthenominalcylindervolumeinlitres.Thisappliestoelectricallyheatedcombinationunitsaswellasotherelectricallyheatedcylinders.
3.0 Vented and unvented systems, including cylinders heated primarily by electricity
a. Cylindersshouldeitherbefactoryfittedwith,orhaveprovisionfor,twothermostaticallycontrolledelectricalheatingelementsorimmersionheaters.
b. Thelowerelementshouldbecapableofheatingupatleast85%ofthecylindercontents.
c. Theupperelementshouldbecapableofheatingatleast60litresofwater.
d. Thelowerelementshouldbeconnectedtoutilisethe‘offpeak’electricitytariffandtheupperforboostoperation.
e. Thevesselshouldbedesignedsuchthatfollowingreheatingto60°Cfromtheoffpeakelement,atleast80%ofthecontentscanbedrawnoffat45°Coraboveataflowrateof0.25l/s.
4.0 Primary stores
a. PrimarystoragesystemsshouldmeettheinsulationrequirementsoftheHotWaterAssociationPerformance specification for thermal stores.
b. UnventedhotwaterstorageproductsshouldcomplywitharelevantstandardassetbyanaccreditedtestbodysuchastheBritishBoardofAgrément,theWaterResearchCouncilorKIWA.
5.0 Labelling
a. Allhotwaterstoragevesselsshouldcarryalabelwiththefollowinginformation:
i. typeofvessel
ii. nominalcapacityinlitres
iii.standingheatlossinkWh/day
iv.heatexchangerperformanceinkW.
b. VentedcopperhotwatercylindersshouldcarryclearlabellingontheproductsuchasaBSIKitemark,registeredfirmstatusorreferencetoanequivalentqualitycontrolscheme.
c. VentedcylinderswhicharenotofcopperconstructionshouldbelabelledascomplyingwiththeheatlossandheatexchangerrequirementsofBS1566-1.
d. Forlabellingofhotwaterstoragevesselsinsolarthermalsystems,seeSection11.
Supplementary information
BS1566-1:2002Copper indirect cylinders for domestic purposes. Open vented copper cylinders. Requirements and test methods.
BS3198:1981Specification for copper hot water storage combination units for domestic purposes.
BSEN12897:2006Water supply. Specification for indirectly heated unvented (closed) storage water heaters.
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Section 4: Electric heating
Table 19 Recommended minimum standards for insulation of pipework in central heating systems with electric boilers
Minimum standard Supplementary information
a. PipesshouldbeinsulatedtocomplywiththemaximumpermissibleheatlossindicatedintheSupplementaryinformationcolumn,andlabelledaccordingly,asfollows:
i. Primarycirculationpipesforheatingcircuitsshouldbeinsulatedwherevertheypassoutsidetheheatedlivingspaceorthroughvoidswhichcommunicatewithandareventilatedfromunheatedspaces.
ii. Primarycirculationpipesfordomestichotwatercircuitsshouldbeinsulatedthroughouttheirlength,subjectonlytopracticalconstraintsimposedbytheneedtopenetratejoistsandotherstructuralelements.
iii.Allpipesconnectedtohotwaterstoragevessels,includingtheventpipe,shouldbeinsulatedforatleast1metrefromtheirpointsofconnectiontothecylinder(ortheyshouldbeinsulateduptothepointwheretheybecomeconcealed).
iv. Ifsecondarycirculationisused,allpipeskepthotbythatcirculationshouldbeinsulated.
b. Wheneveraboilerorhotwaterstoragevesselisreplacedinanexistingsystem,anypipesthatareexposedaspartoftheworkorareotherwiseaccessibleshouldbeinsulatedasrecommendedabove–ortosomelesserstandardwherepracticalconstraintsdictate.
Pipe outside diameter (mm)8
1012152228354254
Maximum heat loss (W/m)7.067.237.357.899. 1 2
10.0711 .0812. 1 914. 1 2
Inassessingthethicknessofinsulationrequired,standardisedconditionsshouldbeassumedinallcompliancecalculations,basedonahorizontalpipeat60°Cinstillairat15°C.
FurtherguidanceonconvertingheatlosslimitstoinsulationthicknessforspecificthermalconductivitiesisavailableinTIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
Insulation of pipework in unheated areas
Itmaybenecessarytoprotectcentralheatingandhotwaterpipeworkinunheatedareasagainstfreezing.Guidanceisavailablein:
• BS5422:2009Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range -40°C to +700°C.
• BREReportNo262 Thermal insulation: avoiding risks, 2002edition.
4.3 Electric heating systems (other than electric boilers serving central heating)Thissectionprovidesguidanceonthefollowingtypesoffixedelectricheatingsystems:
• electricwarmairsystems
• electricpanelheaters
• electricstoragesystemsincludingintegratedstorage/directsystems.
Portable,plug-inappliancesarenotcoveredbythisguide.
Fixedelectricheatingsystems(otherthanwithelectricboilers)shouldmeettheminimumstandardsfortimeandtemperaturecontrolinTable20.
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Table 20 Recommended minimum controls for primary and secondary electric heating systems (other than with electric boilers)
System Control type Minimum standardSupplementary information
Warm air 1.0 Time and temperature control, integral to the heater or external
a. Systemsshouldbeprovidedwith:
i. atimeswitch/programmerandroomthermostat,or
ii. aprogrammableroomthermostat.
2.0 Zone control
a. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttemperaturecontrol,oneofwhichisassignedtothelivingarea.
b. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttemperatureandtimecontrol.Timecontrolmaybeprovidedusing:
i. multipleheatingzoneprogrammers,or
ii. asinglemulti-channelprogrammer,or
iii.programmableroomthermostats,or
iv.separatetimerstoeachcircuit,or
v. acombinationof(iii)and(iv)above.
c. Insingle-storey,open-plandwellingsinwhichthelivingareaisgreaterthan70%ofthetotalfloorarea,sub-zoningoftemperaturecontrolisnotappropriate.
Panel heaters 3.0 Local time and temperature control
a. Timecontrolshouldbebyaprogrammabletimeswitchintegratedintotheapplianceorbyaseparatetimeswitch.
b. Individualtemperaturecontrolshouldbebyintegralthermostatsorbyseparateroomthermostatsorprogrammableroomthermostats.
Panelheatersprovideinstantaneousheat.
Storage heaters
4.0 Charge control
a. Automaticcontrolofinputchargeshouldbeprovided. Chargecontrolistheabilitytodetecttheinternaltemperatureandadjustthechargingoftheheateraccordingly.
5.0 Temperature control
a. Temperaturecontrolshouldbebyadjustingtherateofheatreleasefromtheappliance,usinganadjustabledamperorotherthermostatically-controlledmethod.
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Section 5: Solid fuel heating
Section 5: Solid fuel heating
5.1 Scope of guidanceThissectionprovidesguidanceonmeetingtheenergyefficiencystandardsintheBuildingRegulationsforthefollowingtypesofsolidfuelheatingappliancesandsystemsusedtodeliverprimaryandsecondaryheating:
• batch-fedopenfires
• batch-fedandautomatic-feeddryroomheaters/stoves
• batch-fedlogandmulti-fuelappliances
• automatic-feedpelletstoveswithandwithoutboilers
• batch-fedandautomatic-feedroomheaterswithboilers
• batch-fedcookerswithboilersnotexceeding7.5kW
• batch-fedindependentboilersandautomatic-feedanthracite,woodpellet,woodchipandwoodlogfiredindependentboilers
• centralheatingsystemsusingcertaintypesofsolidfuelappliances.
Theguidancecoversthefollowingtypesofsolidfuel:coal,anthracite,manufacturedsmokelessfuel,dual-fuel,woodlogs,woodpelletsandwoodchips.
5.2 Solid fuel appliances for primary heatingSolidfuelappliancesprovidedwithnewsystemsorasreplacementsinexistingsystemsforprimaryheatingindwellingsshouldhaveanefficiency(grosscalorificvalue)notlessthanspecifiedinTable21forthatcategoryofappliance.
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Table 21 Solid fuel appliance categories and recommended minimum efficiencies
Category Appliance descriptionMinimum efficiency (gross calorific value) Feed
B1 Simpleopenfire–inset 37% Batch
B2 Openfire–freestandingconvector 47% Batch
B3 Openfire–insetconvector 45%(mineralfuels)43%(woodfuels)
C1/2 Openfireandboiler–insetorfreestanding 50% Batch
D1/2/3 Openfirehighoutputboiler–trapeziumandrectangulargrates
63% Batch
D4 Openfirehighoutputboiler–rectangle 63% Batch
E1 Dryroomheater(drystove) 65% Batch/auto
E2 Dryroomheater–woodlogsonly 65% Batch
E3 Dryroomheater–multi-fuel 65% Batch
E4 Dryroomheater–pelletstove 65%partload70%nominalload
Auto
F Roomheaterwithboiler 67%(mineralfuelsandwoodlogs)70%(woodpellets–partload)75%(woodpellets–nominalload)
Batch/auto
G1 Cookerwithoutboilernotexceeding3.5kW 65%(mineralfuels)55%(woodfuels)
Batch
G2 Cookerwithheatingboilerexceeding3.5kW 65%(mineralfuels)60%(woodfuels)
Batch
J2 Independentboiler–woodlogsonly 75% Batch
J3 Independentboiler–multi-fuel 65%(mineralfuels)75%(woodlogs)
Batch
J4 Independentboiler–anthracite 70%upto20.5kW75%above20.5kW
Auto
J5 Independentboiler–wood/pellets/chips 75%nominalload70%partload
Auto
Slowheatreleaseappliances 65% Batch
One-offtiled/mortaredstoves 70% Batch
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Section 5: Solid fuel heating
Supplementary information
Minimum efficiencies
MinimumefficienciesforsolidfuelappliancesarepublishedintheOfficial guide to HETAS approved solid fuel products and services,andonthewebsitewww.hetas.co.uk.Manufacturers’efficiencyfiguresmaybehigherthanthoseindicatedandshouldbeusedwhereindependentlycertifiedagainsttheharmonisedEuropeanStandardsnowinplace.
Carbon emission factors
Solidfuelsincludewoodinvariousforms,differenttypesofcoal,andmanufacturedsolidfuels,andconsequentlythereisarangeofassociatedCO
2emissionfactors.Thesefactorsareasimportantasapplianceefficiencywhenselectingaboiler.
CO2emissionfactors(kgCO
2/kWh)forgenerictypesofsolidfuelgiveninSAP2012Table12are:
Housecoal:traditionalBritishcoal,burnswithsmokyflame Anthracite:mineralfuelwithhighcarboncontent,burnsverycleanly Manufacturedsmokelessfuel:mineralfuelusuallymadefromanthracite Woodlogs:renewablewoodlogseitherpurchasedorfromownland Woodpelletsinbags:mechanicallycompressedsawdust Bulkwoodpellets:asabove,deliveredinbulk Woodchips:chippedwood,processedonsite Dual-fuel:UK‘typicalblend’oflogsandmineralfuelasburntonadual-fuelstove
0.3940.3940.4330.0190.0390.0390.0160.226
Smoke control
Withinlocalauthoritysmokecontrolareas,onlyanthraciteorotherauthorisedsmokelessfuelsmaybeused,unlessthepropertyisfittedwithanexemptedappliance.AnexemptedapplianceisonethathasbeenapprovedbyParliamentaryStatutoryInstrumentforinstallationinsmokecontrolareasandprospectivepurchasersshouldcheckthattheapplianceandintendedfuelarepermitted.Alistofcurrentlyauthorisedfuelsandexemptedappliancesisgivenonthewebsitewww.uksmokecontrolareas.co.uk.
Outsideasmokecontrolarea,housecoalorwoodcanbeburntonnon-exemptedappliances.Woodshouldalwaysbeseasonedtoamoisturecontentappropriatetothedesignandperformanceoftheappliance,forexamplenotexceeding20%inlogwood,toensuremaximumperformanceandlimittheoccurrenceofcondensationanddepositsinthechimneysystem.
Allsolidfuelappliancesrequireappropriatesoot-fireresistantchimneysdischargingathighlevellocationsasdefinedwithintheBuildingRegulations.DetailsofHETAS-approvedchimneyproductsindependentlytestedandapprovedtoacceptedstandardscanbefoundontheHETASwebsite.ThenaturalventilationratesofthesechimneysmaybelessthanthedefaultvalueslistedwithinSAP2012;theuseofthesemoreaccuratevalueswillreduceSAPcalculatedCO
2emissions.
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5.3 Central heating systems using certain types of solid fuel appliancesThissectionprovidesguidanceonthefollowingtypesofsolidfuelapplianceusedtodeliverprimaryheatingaspartofacentralheatingsystem:
• batch-fedopenfireswithhighoutputboilers(appliancetypesD1toD4inTable21)
• batch-fedandautomatic-feedroomheatersandstoveswithboilers(appliancetypeFinTable21)
• batch-fedcookerswithboilers(appliancetypeG2inTable21)
• batch-fedindependentboilersandautomatic-feedanthracite,woodlog,woodpelletandwoodchip-firedindependentboilers(appliancetypesJ2toJ5inTable21).
Unlessstatedotherwise,theguidanceappliesequallytoappliancesthatburnwood,woodpellets,housecoal,manufacturedsmokelessfuelsandanthracite.
Forcentralheatingsystemswithasolidfuelapplianceinstalledaspartofanewsystemorasareplacementcomponentinanexistingsystem:
a. theapplianceshouldbefromHETAScategoriesD,F,GandJinTable21andhaveaminimumefficiency(grosscalorificvalue)whichisnotlessthanthevaluespecifiedforitscategory
b. theratioofroomheattowaterheatshouldbeappropriatefortheroomandtotalproperty.Thiswillrequirereferencetoinstallationpracticeguidelinesandcalculationofroomandpropertyheatloss.AdviceonthisisgivenintheHETASguideandwebsitereferredtoearlier
c. circulation,fuelstorage,hotwaterstorage,systempreparation,watertreatmentandcommissioningshouldbetothestandardsinTable22
d. controlofheatingandhotwatercircuitsshouldbetothestandardsinTable23
e. pipeworkshouldbeinsulatedtothestandardsinTable24.
Supplementary information
Turn-down values (i.e. the ratio of high to low output)
Turn-downratiosaregenerallyverygood(10:1)forautomatic-feedapplianceswithsmallfirebeds.
Turn-downratiosarelessgoodwithlargebatch-fedappliancesunlessthelatterareusedinconjunctionwithahotwateraccumulator.
Automaticappliancesarelikelytorequirelessfrequentrefuelling.Automatic(e.g.electricorgas)ignitionisnowavailableforcertaindesignsandreducesenergyusageattimesoflowdemandbyallowingboilerinterlock.
Someboilershavebothauto-ignitionandfire-extinguishingfeatures.
Link-up systems
Itispossibletoconnecttogethertwoormoreheatingapplianceswithboilers(atleastoneofwhichcanbesolidfuel-fired)tomaximiseflexibilityandefficiency.Forexample,anoilorgasboilercouldbecombinedwithawoodburningstovewithboilersitedinthelivingroom.Thiscombinationwithwoodburningapplianceswillreduceoverallcarbonemissions.Bothsystemsshouldbedesignedtoappropriateinstallationcodes.
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Table 22 Recommended minimum standards for system circulation, fuel storage, hot water storage, system preparation and commissioning for solid fuel central heating
Minimum standard Supplementary information
1.0 System circulation
a. Whereboilerinterlockisavailable,fullypumpedcirculationshouldbechosen.
b. Themanufacturer’sinstructionsonthesizingandpositioningofheatleakradiatorsshouldbefollowed.
c. Solidfuelappliancesshouldnotbefittedtosealedheatingsystemswithexpansionvessels,exceptwherespecificallypermittedbythemanufacturerorwhereathermalstorageinterfacedeviceisused.
Mostsolidfuelcentralheatingsystemsrequireaheatleakradiatortodissipateheatfromthesmoulderingfirebed.Thisiscommonlythebathroomtowel-railandathermosiphonsystemmaybeusedforthiscircuit.Insomecasesafullypumpedsystemreducesefficiencyandshouldnotbeused.
2.0 Fuel storage
a. Provisionshouldbemadeforstorageofreasonablequantitiesoffuelinaconvenientanddrylocation.Thesizeofthestoragewilldependupontherequirementofthehouse.
Nominimumquantityoffuelisspecifiedforsolidmineralfuelbutbunkersgreaterthan250kgarepreferredasbelowthishouseholdersarelikelytopayadeliverypremium.
3.0 Hot water storage
a. VentedcopperhotwaterstoragevesselsshouldcomplywiththeheatlossandheatexchangerrequirementsofBS1566-1:2002orBS3198:1981.
b. VentedcylindersinmaterialsotherthancoppershouldcomplywiththeheatlossandheatexchangerrequirementsofBS1566-1.
c. UnventedhotwaterstoragesystemproductsshouldcomplywithBSEN12897:2006oranequivalentstandard.
d. Unventedsystemsshouldnotbeusedwithgravitycirculation.
e. Primarystoragesystemsshouldmeettheinsulationrequirementsofsection4.3.1or4.3.2oftheHotWaterAssociationPerformance specification for thermal stores.
f. CombinationcylindersshouldcomplywithBS3198andinadditionhaveaheatlossnotexceeding1.6(0.20.51V2/3)kWh/day,whereVisthevolumeofthehotwaterpartofthecylinderinlitres.
g. Allhotwaterstoragevesselsshouldcarryalabelwiththefollowinginformation:
i. typeofvessel
ii. nominalcapacityinlitres
iii.standingheatlossinkWh/day
iv.typeofvessel
v. heatexchangerperformanceinkW.
h. VentedcopperhotwatercylindersshouldcarryclearlabellingontheproductsuchasaBSIKitemark,registeredfirmstatusorreferencetoanequivalentqualitycontrolscheme.
Primary hot water stores
Thesecanhaveamajorroletoplayintheinstallationofsolidfuel.Themainreasonfortheiruseistostoretheheatgeneratedduringslumberperiodsbutwhereunventedstoragecylindersareusedtheyalsoprovidemainspressurehotwaterandpossiblefrostprotection(viaelectricimmersionheaters)forthesolidfuelsystem.Domestichotwateroutlettemperatureistobecontrolledatasafelevel.Becauseofthehigherthannormalstoragetemperaturesitisveryimportantthatstoresarewellinsulated.
TheHWAthermalstoragespecificationisavailableforfreedownloadfromwww.hotwater.org.uk.
British Standards
BS1566-1:2002Copper indirect cylinders for domestic purposes. Open vented copper cylinders. Requirements and test methods.
BS3198:1981Specification for copper hot water storage combination units for domestic purposes.
BSEN12897:2006Water supply. Specification for indirectly heated unvented (closed) storage water heaters.
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Table 22 Recommended minimum standards for system circulation, fuel storage, hot water storage, system preparation and commissioning for solid fuel central heating (continued)
Minimum standard Supplementary information
4.0 System preparation and water treatment
a. Centralheatingsystemsshouldbethoroughlycleanedandflushedoutbeforeinstallinganewboiler.
b. Duringfinalfillingofthesystemachemicalwatertreatmentformulationshouldbeaddedtotheprimarycircuittocontrolcorrosionandtheformationofscaleandsludge.ReasonableprovisionwouldbetofollowtheguidanceonhowtoprepareandcommissionsystemsgiveninBS7593:2006Code of practice for treatment of water in domestic hot water central heating systems.
c. Installersshouldalsorefertotheboilermanufacturer’sinstallationinstructionsforappropriatetreatmentproductsandspecialrequirementsforindividualboilermodels.
d. Wherethemainstotalwaterhardnessexceeds200partspermillion,provisionshouldbemadetotreatthefeedwatertowaterheatersandthehotwatercircuittoreducetherateofaccumulationoflimescale.
BS7593notesthat“naturallysoftwatersoflowalkalinityorthosesuppliedviaabase-exchangeresinsoftenerhaveanincreasedpotentialforcorrosion,and,iftheyareusedinanycentralheatingsystem,acorrosioninhibitorspecificallyformulatedforthepurposeshouldbeaddedandproperlymaintained.”Manufacturersshouldbeconsultedforadvice,payingparticularattentiontodosagelevels.
Specialradiatorvalvesareavailablethatwillsealofftheradiatoraswellastheheatingcircuittopreventlossofinhibitorwhenremovingaradiatorforserviceormaintenance.
Afiltercanalsobefittedtothecentralheatingcircuittohelpmaintaintheefficiencyandreliabilityofthesystem.
5.0 Commissioning
a. Oncompletionoftheinstallationofaboilerorhotwaterstoragesystem,togetherwithassociatedequipmentsuchaspipework,pumpsandcontrols,theequipmentshouldbecommissionedinaccordancewiththemanufacturer’sinstructions.Theseinstructionswillbespecifictotheparticularboilerorhotwaterstoragesystemused.
b. Theinstallershouldexplainfullytotheuserhowtooperatethesysteminanenergyefficientmanner,andleavebehindanyusermanualsprovidedbymanufacturers.
Onlypersonswhoarecompetentshouldcarryouttheinstallation,e.g.installerswhoareregisteredwithHETAS.SuchpersonswillcertifythattheyhavecarriedoutinstallationandcommissioninginaccordancewithrequirementsintheBuildingRegulationsandinthemanufacturer’sinstructions(whichmaybemorestringent).
Notethatthedeliveryofwoodorcoalwithoutappropriatedocumentationintoasmoke-controlareaisanoffenceundertheCleanAirAct.
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Section 5: Solid fuel heating
Table 23 Recommended minimum controls for solid fuel central heating systems
Minimum standard
All appliances, except open fires
1.0 Burning rate
a. Thermostaticcontroloftheburningrate.
Automatic-feed appliances
2.0 Zoning
a. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttemperaturecontrol,oneofwhichisassignedtothelivingarea.
b. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttemperatureandtimecontrol.
c. Forsingle-storey,open-plandwellingsinwhichthelivingareaisgreaterthan70%ofthetotalfloorarea,sub-zoningoftemperaturecontrolisnotappropriate.
3.0 Time control of space and water heating
a. Timecontrolofspaceandwaterheatingshouldbeprovidedby:
i. afullprogrammerwithseparatetimingtoeachcircuit,or
ii. twoormoreseparatetimersprovidingtimingcontroltoeachcircuit,or
iii.programmableroomthermostatstotheheatingcircuits,withseparatetimingofthehotwatercircuit.
4.0 Temperature control of space heating
a. Separatetemperaturecontrolofzoneswithinthedwellingshouldbeprovidedusing:
i. roomthermostatsorprogrammableroomthermostatsinallzones,or
ii. aroomthermostatorprogrammableroomthermostatinthemainzone,andindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs),or
iii.acombinationof(i)and(ii)above.
5.0 Temperature control of domestic hot water
a. Acylinderthermostatandazonevalveorthree-portvalveshouldbefittedtocontrolthetemperatureofstoredhotwater.
b. Non-electrichotwatercontrollersshouldnotbeused.
c. Wherepermittedbythemanufacturer,thecylinderthermostatshouldbewiredtoprovideaboilerinterlock.
Supplementary information
Boilerinterlock,providedbyawiringarrangementtopreventthesystemfromoperatingwhenthereisnodemandforheat,shouldonlybefittedifrecommendedbythemanufacturer.
Insomesimplebatch-fedorautomaticappliances(withoutheatstoresorwithoutautomaticignition),itisnotpossibletoswitchofftheheatoutputcompletely,buttheapplianceoutputcanbeloweredtoaminimumtoreducefuelconsumption.
Inmostsolidfuelsystemstheroomthermostatwillswitchoffthepump,whichinturnwillcausetheboilertooperateatminimumoutput.
Someautomaticsolidfuelsystemscanbefittedwithweathercompensation,andincorporatemulti-zonecontrol.Itisimportanttoseekguidancefromthemanufacturer,especiallyiftheheatingpackageistoincludeotherfuels.
Controlsmaybeprovidedbyanyboilermanagementcontrolsystemthatmeetsthespecifiedzoning,timingandtemperature,andboilerinterlockcontrolrequirements.
Thelevelofsophisticationshouldgenerallybeappropriatetoandcompatiblewiththeappliance.Thehighestlevelsareonlyappropriatetoapplianceswithautomaticignition.
Asfarasitispracticableandeconomictodosowhenworkingonexistingsystems,controlsshouldbeupgradedtothelevelsdefinedfornewsystems.
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Table 24 Recommended minimum standards for insulation of pipework in solid fuel central heating systems
Minimum standard Supplementary information
a. PipesshouldbeinsulatedtocomplywiththemaximumpermissibleheatlossindicatedintheSupplementaryinformationcolumn,andlabelledaccordingly,asfollows:
i. Primarycirculationpipesforheatingcircuitsshouldbeinsulatedwherevertheypassoutsidetheheatedlivingspaceorthroughvoidswhichcommunicatewithandareventilatedfromunheatedspaces.
ii. Primarycirculationpipesfordomestichotwatercircuitsshouldbeinsulatedthroughouttheirlength,subjectonlytopracticalconstraintsimposedbytheneedtopenetratejoistsandotherstructuralelements.
iii.Allpipesconnectedtohotwaterstoragevessels,includingtheventpipe,shouldbeinsulatedforatleast1metrefromtheirpointsofconnectiontothecylinder(ortheyshouldbeinsulateduptothepointwheretheybecomeconcealed).
iv. Ifsecondarycirculationisused,allpipeskepthotbythatcirculationshouldbeinsulated.
b. Wheneveraboilerorhotwaterstoragevesselisreplacedinanexistingsystem,anypipesthatareexposedaspartoftheworkorareotherwiseaccessibleshouldbeinsulatedasrecommendedabove–ortosomelesserstandardwherepracticalconstraintsdictate.
Pipe outside diameter (mm)8
1012152228354254
Maximum heat loss (W/m)7.067.237.357.899. 1 2
10.0711 .0812. 1 914. 1 2
Inassessingthethicknessofinsulationrequired,standardisedconditionsshouldbeassumedinallcompliancecalculations,basedonahorizontalpipeat60°Cinstillairat15°C.
FurtherguidanceonconvertingheatlosslimitstoinsulationthicknessforspecificthermalconductivitiesisavailableinTIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
Insulation of pipework in unheated areas
Itmaybenecessarytoprotectcentralheatingandhotwaterpipeworkinunheatedareasagainstfreezing.Guidanceisavailablein:
• BS5422:2009 Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range -40°C to +700°C.
• BREReportNo262 Thermal insulation: avoiding risks, 2002edition.
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Section 5: Solid fuel heating
5.4 Solid fuel appliances for secondary heatingSolidfuelappliancesinnewandexistingdwellingsthatprovidesecondaryheatingandarenotpartofacentralheatingsystemshouldhavetheminimumefficiency(grosscalorificvalue)specifiedinTable21forthecategoryofappliance.
Supplementary information
Minimum efficiencies
MinimumefficienciesforsolidfuelappliancesarepublishedintheOfficial guide to HETASapproved solid fuel products and services,andonthewebsitewww.hetas.co.uk.Manufacturers’figuresmaybehigherbutshouldbeusedonlywhereindependentlycertifiedagainsttheharmonisedEuropeanStandardsnowinplace.
Appliance types
Thetypesofappliancemostsuitableforprovidingsecondaryheatingare:
• Open-fire with high output boiler, when used with ‘link-up’
• Small solid fuel room heaters (stoves), especially wood-fired.
Thesecanbeadedicatedwoodburnerorburnlogsinamulti-fuelapplianceorusepellets.Theycanbematchedwithamainheatingsystemfiredbythesameoradifferentprimaryfueloroff-peakelectricitytoreducecarbonemissions,especiallywood-fired,withorwithoutthermostaticcontrol.Manydesignscanprovideheatingduringpowercuts.Mineralfuelappliancescanbechosenbuttheattentionofdesignersisdrawntotheprobableneedtosupplyadditionalmeasures,asthecarbonemissionvaluesofthesetendtobehigh.Mineralfuelappliancesmayoftenhaveslightlyhigherefficienciesthantheirwoodburningcounterparts.Multi-fuelroomheaterscanenabletheusertoburnrenewablewoodaswellasanalternativetomineralfuelsoutsidesmokecontrolareas.
• Small solid fuel stoves with boilers
Theefficiencyofthesecanbehigherthanthatofdryappliances.Theycanbeintegratedwiththeprimarywetheatingsystem.Multi-fuelappliancesenablethehouseholdertoburnrenewablewoodoutsidesmokecontrolareas.
• Range cookers
Typicallyapplianceswhichareinstalledina‘livingarea’andaredesignedtoprovidesomeusefulheatfromtheircaseintothespaceinwhichtheyarelocated.Theyareavailableinavarietyofshapesandsizesandcanincorporateaboilerwhichcanbeconnectedtodual-fuelintegratedsystems(e.g.link-up).Multi-fuelversionsarealsoavailable.
• Open fires (HETAS categories B1, B2 and B3)
Whererequested,thesecanbefitted.Theydonothavethermostaticcontroloftheburningrateandsohavelowerefficiencies,buttheyareabletoburnwoodlogswithcorrespondinglylownetcarbonemissions.Itmustbestressedthatlargeopenfireswithalargefreefacearea(openingwidthtimesopeningheight)usuallyhaveaneedforventilationwellinexcessofthatavailableinapropertybuilttomodernstandardsofairtightness.Thisislikelytoleadtosevereoperationalproblemsunlessspecialstepsaretakentoprovidetherequiredairsupply.Theuseofsuchlarge(simple)openfiresispenalisedintheSAPcalculations.
Controls
Whereverpossible,solidfuelappliancesshouldhavethermostaticcontrol.(TheseareusuallyintegraltoappliancesincategoriesE,FandG.)Controlsshouldbeappropriatetothelevelofsophisticationoftheappliance;automaticappliancescanbenefitfromadvancedcontrols.
Provision of fuel storage
Thequantityoffuelconsumedbysecondaryheatingappliancesislikelytobelessthan1tonneperyear.Howeveritshouldbestoredinadryandconvenientlocation.
Smoke control areas
Thelocationoftheappliancewithinorwithoutasmokecontrolareaiscriticaltotheprocessofoptimisingthechoiceofapplianceandfuel.
Forfurtherinformationonsolidfuelappliances,seeCE47EnergyEfficiencyBestPracticeinHousing – Domestic heating by solid fuel: Boiler systems.
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Standards
BSEN12809:2001+A1:2004+AC:2006/2007Residential independent boilers fired by solid fuel. Nominal output up to 50 kW. Requirements and test methods.
BSEN12815:2001+A1:2004/2006/2007Residential cookers fired by solid fuel. Requirements and test methods.
BSEN13229:2001+A1:2003+A2:2004+AC:2006/2007Inset appliances including open fires fired by solid fuel. Requirements and test methods.
BSEN13240:2001+A2:2004+AC2006/2007Room heaters fired by solid fuel. Requirements and test methods.
BSEN15250:2007Slow heat release appliances fired by solid fuel. Requirements and test methods.
BSEN15544:2009One-off tiled/mortared stoves. Calculation method.
BSEN14785:2006Residential space heating appliances fired by wood pellets.
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Section 6: Community heating
Section 6: Community heating
6.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofcommunityheatingsystemsfordwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
Acommunityheatingsystemisonethatsuppliesheattoanumberofdwellingsfromacommonheatsource.Asystemmayheatasmallblockofflatsoralargenumberofbuildings.
Theguidanceinthissectionappliestosystemsthat:
• supply15ormoredwellingsfromacentralboiler,orfromalowcarbonsourcesuchascombinedheatandpower(CHP),biofuels,heatpumpsandsolarpanels
• distributeheatfromthecentralsourceusingawetradiatorsystem(althoughwarmairheatingandunderfloorheatingsystemsmayalsobeused).
Meteringrequirementsforcommunityheatingschemesarebeingintroduced,startinginJune2014,asaresultoftheEUEnergyEfficiencyDirective.SeetheDECCwebsitefordetailsoftherequirementsandthetechnicalstandardsthatapply(forexampleonmeterspecifications):https://www.gov.uk/decc.
6.2 New and existing community heating schemesThecentralheatsourceshouldcomplywiththerequirementsintheNon-Domestic Building Services Compliance Guideexceptwherespecifiedinthissection.
Guidanceisprovidedfortwoscenarios:
• connectingdwellingstoanewcommunityheatingscheme
• connectingdwellingstoanexistingcommunityheatingscheme.
Connecting dwellings to a new community heating scheme
Newcommunityheatingsystemsforbothnewandexistingdwellingsshouldmeettheminimumstandardsfor:
a. energyefficiencyinTable25
b. lowcarbonheatsourcesinTable26
c. systemcontrolinTable27
d. hotwaterproduction,storageandtreatment,heatmeteringandcommissioninginTable28
e. insulationofpipeworkinTable29andTable30.
Connecting dwellings to an existing community heating scheme
Whereexistingcommunityheatingsystemsareconnectedtoneworexistingdwellings:
a. Iftheexistingcommunityheatingsystemisinneedofreplacementorimprovement,astudyshouldbecarriedouttoassesstheeconomicandenvironmentalbenefitsofarangeofoptions,including
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theuseofCHPandotherlowcarbonheatsources,especiallywhereindividualheatingsystemsarebeingconsideredasanalternativetocontinuingwiththecommunityheatingsystem.
b. ReplacementboilersshouldmeettheminimumstandardsforboilerefficiencyintheNon-Domestic Building Services Compliance Guide (availablefromwww.planningportal.gov.uk/approveddocuments/PartL>Associateddocuments).
c. Ifthermalenergyispurchasedfromanexistingdistrictorcommunityheatingsystem,anassessmentofthecarbonintensityoftheschemeshouldbecarriedout.Emissionfactorsshouldbedeterminedbasedontheparticulardetailsofthescheme,butshouldtakeaccountoftheannualaverageperformanceofthewholesystem–thatis,ofthedistributioncircuitsandalltheheatgeneratingplant,includinganyCHP,andanywasteheatrecoveryorheatdumping.Thecalculationofthedwellingcarbondioxideemissionrateshouldbecarriedoutbyasuitablyqualifiedperson,whoshouldexplainhowtheemissionfactorswerederived.
d. ControlsshouldmeettheminimumstandardsinTable27.
e. PipeworkinsulationshouldmeettheminimumstandardsinTable29andTable30.
Table 25 Recommended minimum standards for the design of community heating systems to maximise efficiency of heat generation and minimise energy use by pumps
Minimum standard Supplementary information
1.0 Boilers
a. Boiler-onlycommunityheatingsystemsfornewdwellingsmaybeusedprovidedthatthetargetcarbondioxideemissionrate(TER)forthedwellingisnotexceeded.
b. BoilersshouldbeselectedtocomplywiththeboilerefficiencyrequirementsoftheNon-Domestic Building Services Compliance Guide.
Whencalculatingthecarbondioxideemissionrate,thetypeandquantityoffuelusedandalsotheelectricityneededtooperatethecentralplantandpumpsshouldbetakenintoaccount.
Forsystemsusingcondensingboilers:
• Toachievehighboilerefficiency,returntemperaturesfromradiatorcircuitsshouldbebelow50°C.
• Whereinstantaneousplateheatexchangersareusedtoproducehotwaterinindividualdwellingsthereturntemperatureselectedshouldbelessthan40°C.
• Wherehotwatercylindersareusedthecoilsizeshouldbesuchastorequireaflowratethatresultsinanominalreturntemperatureoflessthan40°Cwhilemeetingtherequiredheat-uptime.
• Wherehotwaterisproducedcentrally(e.g.ineachblockofdwellings)returntemperaturesshouldbebelow40°C.
2.0 Controlling the sequencing and firing of boilers
a. ControlsforboilersshouldfollowtheguidanceintheNon-Domestic Building Services Compliance Guide,butwithoutoptimumstart.
Settingoccupationtimesisnotgenerallypossibleforagroupofdwellingsandsooptimumstartcontrolsarenotarecommendation.
3.0 Minimising energy use by pumps
a. Fornewcommunityheatingsystems,thedesigntemperaturedifferenceforthecommunityheatingprimarycircuitshouldbegreaterthan20°C.
b. Variablevolumecontrolsystemsshouldbeusedtoreducethevolumeofwaterandthepressuredifferencerequiredfromthepumpsunderpartload.
Pumpingenergycanbeminimisedbyoptimisingoperatingtemperaturesandpipesizestoreduceinstalledpumppower.
Totakefulladvantageofvariablevolumesystems,variablespeedpumpsshouldbeinstalledandcontrolledtodelivertherequiredpressuredifferencetosuittheload.
FurtherguidanceisprovidedinBSRIAApplicationGuideAG16/2002–Variable-flow water systems: design, installation and commissioning guidance.
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Table 26 Recommended minimum standards for design of low carbon heat sources where these are included in community heating systems
Minimum standard Supplementary information
1.0 Low carbon heat sources
a. Nominimumstandard,butseeSupplementaryinformation.
Communityheatingsystemscanbedesignedtouselowcarbonheatsourcestomeetallorpartoftheheatdemand,whichmayenablesomerelaxationoftheU-valuesthatwouldotherwiseberequired.
2.0 Biofuels
a. Nominimumstandard,butseeSupplementaryinformation.
BiofuelscanbeusedtoprovideheatfromboilersystemsorasafuelforCHPsystems.
Considerationshouldbegiventooperationandmaintenanceoftheplanttoensurealonglifeandtopreventalaterreplacementbyaconventionalfuelsystem.
Whereabiofuelboileristobeusedinconjunctionwithconventionallyfuelledheatingboilersorelectricheating,areasonableminimumproportionoftheannualheatsupplyfrombiofuelswouldbe45%oftheannualheatdemand(space,domestichotwaterandprocessheating).
3.0 Combined heat and power (CHP)
a. WhereCHPisusedinconjunctionwithboilerplant,thecontrolsystemshouldensurethat,asfarasispracticable,theCHPplantoperatesastheleadheatsource.
CHPcapacityshouldbeoptimisedtomeettherequiredeconomicandenvironmentalobjectives.
AreasonableminimumproportionoftheannualheatsupplyfromCHPwouldbe45%oftheannualheatdemand(spaceanddomestichotwaterheating).
TomaximisetheuseofCHPheatovertheyear,considerationshouldbegiventotheuseofthermalstoragetomeetpeaks,especiallyintheearlymorningperiod.
TheproceduregiveninSAP2012shouldbeusedtocalculatethecarbondioxideemissionsfromCHPsystems.
4.0 Heat pumps
a. Nominimumstandard,butseeSupplementaryinformation.
Heatpumpscanbeusedasaheatsourceforcommunityheatingsystems.SelectionofoperatingtemperaturestooptimisetheefficiencyofthecommunityheatingsystemandachievehighCOPsisimportantifcarbondioxideemissionsaretobereduced.Thismayinvolvetheuseofunderfloorheatingandtheprovisionofdomestichotwaterbyothermeans.
Whereheatpumpsareinstalledinconjunctionwithheatingboilers,areasonableminimumproportionoftheannualheatsupplyfromtheheatpumpwouldbe45%oftheannualspaceheatingdemand.
5.0 Solar
a. Nominimumstandard,butseeSupplementaryinformation.
Solarthermalpanelscanbeusedastheheatsourceforacentraliseddomestichotwatersystem.
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Table 27 Recommended minimum controls for community heating systems within dwellings
Control type Minimum standard Supplementary information
1.0 Zoning
a. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttemperaturecontrol,oneofwhichisassignedtothelivingarea.
b. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenttemperatureandtimecontrol.
Insingle-storey,open-plandwellingsinwhichthelivingareaisgreaterthan70%ofthetotalfloorarea,sub-zoningoftemperaturecontrolisnotappropriate.
2.0 Time control of space heating
a. Timecontrolofspaceheatingmaybeprovidedby:
i. afullprogrammer,or
ii. twoormoreseparatetimersprovidingtimingcontroltoeachzone,or
iii.programmableroomthermostatstotheheatingcircuits.
b. Fordwellingswithatotalfloorarea150m2,timecontrolfortheseparatespaceheatingzonescanbeprovidedusing:
i. multipleheatingzoneprogrammers,or
ii. asinglemulti-channelprogrammer.
Wherethehotwaterisproducedinstantaneously,suchaswithaplateheatexchanger,timecontrolisonlyrequiredforspaceheatingzones.
TimecontrolofdomestichotwaterheatingusingacylinderisnotconsideredessentialforcommunityheatingandcouldbeadisadvantagewithCHP-basedsystems,increasingthemorningpeakdemandandhencecausingmoreuseoftheboilerthannecessary.
3.0 Temperature control of space heating
a. Separatetemperaturecontrolofzoneswithinthedwellingshouldbeprovidedusing:
i. roomthermostatsorprogrammableroomthermostatsinallzones,or
ii. aroomthermostatorprogrammableroomthermostatinthemainzone,andindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs)onallradiatorsintheotherzones,or
iii.acombinationof(i)and(ii)above.
ControlvalvesandTRVsshouldbetwo-porttypetoreduceflowratesunderpartload.
DifferentialpressuresacrosscontrolvalvesandTRVsshouldbelimitedtoensurethatthecontrolvalvesworkeffectivelyandmaintainshut-off.
4.0 Temperature control of domestic hot water
a. Temperaturecontrolofthedomestichotwaterserviceshouldbeprovidedusingtwo-portcontrolvalves,eitherelectricallyoperatedordirect-acting.
Whereinstantaneousheatexchangersareusedthecontrolvalveshouldbeselectedtomaintainsteadytemperatures(5°C)forarangeofdraw-offratesandprimarydifferentialpressures.Toreducetheincidenceofscaling,thecontrolvalveshouldshutofftheprimaryflowwhenthereisnodomestichotwaterdrawoff.
Asmallintermittentflowisanadvantagetomaintainthetemperaturewithintheheatexchangersoastoprovidemorerapidheatup.
5.0 Limitation of maximum flow rate into building or dwelling
a. Themaximumdesignflowrateintothedwellingheatingsystemshouldbelimitedbysuitablecontrolandbalancingvalvestomaintaintheoverallbalanceinthenetworkandtoavoidexcessivepumpingenergy.
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Table 28 Recommended minimum standards for domestic hot water (DHW) production, storage and water treatment, heat meters and commissioning for community heating
Minimum standard Supplementary information
1.0 DHW production and storage
a. Thehotwatersystemshouldbecontrolledusingvariablevolumecontrolprinciplesandbedesignedtomaintainlowreturntemperaturesintheprimarycommunityheatingcircuit.
Hotwatercanbeproducedinfourwaysincommunityheatingsystems:
• inindividualdwellingsusingindirectstoragecylinders
• inindividualdwellingsusinginstantaneousplateheatexchangers
• centrallyusingstoragecalorifierswitheitheranindirectcoiloranexternalplateheatexchanger
• centrallyusinganinstantaneousplateheatexchanger.
Inselectingthesystem,considerationshouldbegivento:
• theimpactonreturntemperaturesinthecommunityheatingsystem
• theimpactonflowratesinthecommunityheatingsystem
• theimpactonheatdemandprofilesandcompatibilitywiththeheatsource
• standinglossesfromstoragecylinders/calorifiersandtheimpactonenergyuse
• thequalityofserviceprovidedintermsofflowrateandtemperaturecontrol
• theadvantagesofhavinglocalstorageintermsofsecurityofsupply.
Wherethenetworkisextensiveandhotwaterproductioniscentralised,atwo-stagewaterheatingsystemcanbeusedtodeliverlowreturntemperatures.Inthisdesignthereturnwaterfromthespaceheatingcircuitisusedtopre-heatthecoldfeedtothedomestichotwater.
2.0 Water treatment
a. Asuitablesystemforintroductionofwatertreatmentchemicalsintothecommunityheatingsysteminacontrolledmannerwithfacilityformonitoringofwaterqualityshouldbeprovided.
Asuitablelong-termprogrammeofwatertreatmentisessentialtopreservethelifeofthecommunityheatingsystembylimitinginternalcorrosion.
Additionalchemicalandphysicaltreatmentshouldbeevaluatedespeciallyforlargersystems,including:
• removalofoxygenbyphysicalmeans
• softenedwatersupply
• side-streamfiltration
• biocide.
3.0 Heat meters
a. Provisionshouldbemadeinthedesignforincludingheatmeterseitheratthetimeofinstallationoratalaterdatewithoutmajorpipeworkchanges.
TheEnergyEfficiencyDirectivewillsetstrongerrequirements.Forup-to-dateinformation,seehttps://www.gov.uk/decc
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Table 28 Recommended minimum standards for domestic hot water (DHW) production, storage and water treatment, heat meters and commissioning for community heating (continued)
Minimum standard Supplementary information
4.0 Commissioning
a. Thecommunityheatingsystemshouldbecommissionedsothatthedesignvolumeflowratesaresuppliedtoeachdwellingandthereisnoexcessivebypassingofwaterthatwouldleadtohigherpumpingenergyuse.
b. Theflowratesinindividualheatemittersshouldbebalancedusingappropriatereturntemperaturesorbyusingcalibratedcontrolvalves.
c. Thesystemswithinthedwellingsshouldbedemonstratedtotheresidentandsuitableinformationprovidedontheoperationofthecontrols.
Wherethecentralheatsourceincludesalowcarbonheatsource,thecontrolsystemshouldbeprovenbydemonstratingthatthelowcarbonheatsourcewillnormallyactastheleadheatsource.
Table 29 Recommended minimum standards for insulation of internal pipework in community heating systems
Minimum standard Supplementary information
a. PipesshouldbeinsulatedtocomplywiththemaximumpermissibleheatlossindicatedintheSupplementaryinformationcolumn,andlabelledaccordingly,asfollows:
i. Primarycirculationpipesforheatingcircuitsshouldbeinsulatedwherevertheypassoutsidetheheatedlivingspaceorthroughvoidswhichcommunicatewithandareventilatedfromunheatedspaces.
ii. Primarycirculationpipesfordomestichotwatercircuitsshouldbeinsulatedthroughouttheirlength,subjectonlytopracticalconstraintsimposedbytheneedtopenetratejoistsandotherstructuralelements.
iii.Allpipesconnectedtohotwaterstoragevessels,includingtheventpipe,shouldbeinsulatedforatleast1metrefromtheirpointsofconnectiontothecylinder(ortheyshouldbeinsulateduptothepointwheretheybecomeconcealed).
iv. Ifsecondarycirculationisused,allpipeskepthotbythatcirculationshouldbeinsulated.
b. Wheneveraboilerorhotwaterstoragevesselisreplacedinanexistingsystem,anypipesthatareexposedaspartoftheworkorareotherwiseaccessibleshouldbeinsulatedasrecommendedabove–ortosomelesserstandardwherepracticalconstraintsdictate.
Pipe outside diameter (mm)8
1012152228354254
Maximum heat loss (W/m)7.067.237.357.899. 1 2
10.0711 .0812. 1 914. 1 2
Inassessingthethicknessofinsulationrequired,standardisedconditionsshouldbeassumedinallcompliancecalculations,basedonahorizontalpipeat60°Cinstillairat15°C.
FurtherguidanceonconvertingheatlosslimitstoinsulationthicknessforspecificthermalconductivitiesisavailableinTIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
Insulation of pipework in unheated areas
Itmaybenecessarytoprotectcentralheatingandhotwaterpipeworkinunheatedareasagainstfreezing.Guidanceisavailablein:
• BS5422:2009 Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range -40°C to +700°C.
• BREReportNo262 Thermal insulation: avoiding risks, 2002edition.
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Table 30 Recommended minimum standards for insulation of external pipework in community heating systems
Minimum standard Supplementary information
a. CommunityheatingpipeworkshouldbeinsulatedtothestandardsdefinedinBSEN253forpre-insulatedpipesortoanequivalentperformanceforconventionallyinsulatedpipes.
Communityheatingpipeworktypicallyusespre-insulatedburiedpipesystems.MinimuminsulationthicknessesaredefinedinEuropeanstandards.Wherepipeworkisrunabovegroundthepipeinsulationperformanceshouldbeatleastashighasthatusedintheburiedpartofthesystem.Enhancedinsulationstandardsshouldbeevaluatedwherecommunityheatingissuppliedonlyfromfossil-fuelledboilersorwhereflowtemperaturesover100°Carebeingused.
Designing for minimum heat losses
Heatlossescanbereducedbyoptimisingoperatingtemperaturesinconjunctionwiththeneedtominimisepumpingenergy.Variablevolumecontrolsystemswillassistinmaintaininglowreturntemperatures.Whilesomebypassesmaybeneededtomaintainthesysteminahotconditionreadytomeetthedemand,theseshouldbecontrolledtotheminimumflowneeded.Theuseoftemperaturecontrolledbypassvalveswherethebypassonlyoperateswhenflowtemperaturehasdroppedbelowasetlevelisrecommended.
Allpipeworkshouldbeinsulatedtopreventuncontrolledheatlosswhenpassingthroughcommunalspacesthatmayotherwisesufferfromoverheating.
Supplementary information
GoodPracticeGuideGPG234Guide to community heating and CHP – Commercial, public and domestic applications.AvailablefromtheCarbonTrust.
BSEN13941:2009+A1:2010Design and installation of pre-insulated bonded pipe systems for direct heating.
BSEN14419:2009District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Surveillance systems.
BSEN253:2009+A1:2013District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Pipe assembly of steel service pipe, polyurethane thermal insulation and outer casing of polyethylene.
BSEN448:2009District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Fitting assemblies of steel service pipes, polyurethane thermal insulation and outer casing of polyethylene.
BSEN488:2011District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Steel valve assembly for steel service pipes, polyurethane thermal insulation and outer casing of polyethylene.
BSEN489:2009District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Joint assembly for steel service pipes, polyurethane thermal insulation and outer casing of polyethylene.
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Section 7: Underfloor heating
7.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofunderfloorheatingsystemsinnewdwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
Theguidancecoverstheuseofhotwaterpipesorelectricheatingelementsastheunderfloorheatsource.
7.2 Underfloor heating in new dwellingsUnderfloorheatinginnewdwellingsshouldmeettheminimumstandardsfor:
a. systemcontrolandsafeoperatingtemperaturesinTable31
b. floorinsulationandsystemdesigntominimisedistributionlossesinTable32
c. inthecaseofelectricunderfloorheatingsystemsinnewdwellings,constructionandcontrolsinTable33.
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Table 31 Recommended minimum standards for control of wet and electric underfloor heating systems
Minimum standard Supplementary information
1.0 System temperature control: wet and electric underfloor heating systems
a. Allfloorheatingsystems,whetherwarmwaterorelectric,shouldbefittedwithcontrolstoensuresafeandcomfortableoperatingtemperatures.
b. Topreventdamagetofloorsandoccupantdiscomfort,thetemperatureoftheflowwaterfromwarmwatersystemsconnectedtoahightemperature(60°C)heatsourceshouldbecontrolledusing:
i. multi-portmixingvalvesandthermo-mechanicalorthermo-electricactuators
ii. aseparatehigh-limitthermostat.
c. ElectricfloorheatingsystemsshouldcomplywiththerulesinBS7671:2008+A1:2011Requirements for electrical installations,Section753,Floor and ceiling heating systems,forprotectionagainstelectricshockandthermaleffects,andforselectionandinstallationofequipment.
Mixedsystemswithradiatorsandunderfloorheatingconnectedtoacommonhightemperatureheatsourcemaybenefitfrombeingoperatedatthesamelowwatertemperature.
Foroptimumlong-termefficiency,considerusingweathercompensatingcontrollerswiththermo-electricmixingvalves.
2.0 Room temperature control: wet and electric underfloor heating systems
a. Eachroomshouldhaveitsownthermostat,sensororprogrammablethermostat.
b. Wheretwoadjacentroomshaveasimilarfunction–forexampleakitchenandautilityroom–itmaybeappropriateforbothroomstoshareasingletemperaturecontrol.
3.0 Time control: wet and electric underfloor heating systems
a. Dwellingswithatotalfloorareaupto150m2shouldhaveatleasttwospaceheatingzoneswithindependenttemperaturecontrol,oneofwhichisassignedtothelivingarea.
b. Dwellingswithatotalfloorarea150m2shouldhaveatleasttwospaceheatingzoneswithindependenton/offtimeandtemperaturecontrol.
c. Forsingle-storey,open-plandwellingsinwhichthelivingareaisgreaterthan70%ofthetotalfloorarea,sub-zoningoftemperaturecontrolisnotappropriate.
d. Thickscreedfloorheatingsystems(65mm)shouldhavefacilitiesforautomaticsetbackofroomtemperaturetoalowerlevelatnightorduringunoccupiedperiods.
Facilitiesforautomaticsetbackofroomtemperaturetoalowerlevelatnightorduringunoccupiedperiodsarerecommendedforbothelectricandwarmwatersystems.
4.0 Boiler control: wet underfloor heating systems only
a. Theheatingsystemcontrolsshouldbeconnectedsothatwhenthereisnodemandforheat,theheatsourceandpumpareswitchedoff.
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Table 32 Recommended minimum standards for floor insulation and minimising distribution losses in wet and electric underfloor heating systems
Minimum standard Supplementary information
1.0 Exposed ground floors
a. Groundfloorsonearth,orsuspendedfloorsincontactwithoutsideair,shouldbeinsulatedtolimitdownwardheatloss,duetothethermalresistanceoftheappliedfloorfinish,tonotmorethan10W/m2.
b. Whenheatoutputisnotknownbutthefloorfinishisspecified,theamountofsystemthermalinsulationneededmaybecalculatedbasedonthesumofthethermalresistanceofthefloorfinishandtheunderlyingheatedlayer,multipliedby10.
c. Floorheatingsystemsintendedforcyclicaloperationorinstalledoverunheatedroomsshouldbeseparatedfromthestructuralfloorbyalayerofthermalinsulationwithathermalresistanceofatleast1.25(m2.K)/W.
2.0 Intermediate floors with heated rooms below: wet systems
a. Theintermediatefloorshouldhaveaseparatinglayerofsystemthermalinsulationwiththermalresistanceasin1.0babove,ornotlessthan0.75(m2.K)/WasspecifiedinBSEN1264-4.
Partyfloorsofapartmentswithunderfloorheatingaredirectlycoupledtotheheatingelements,sothermalinsulationisimportant.Inhigh-riseapartments,resistancevaluesmayneedtoexceedthosespecified.
3.0 Intermediate floors with heated rooms below: electric systems
a. Theintermediatefloorshouldhaveaseparatinglayerofsystemthermalinsulationwiththermalresistanceasin1.0babove,ornotlessthan0.5(m2.K)/W.
4.0 System design to minimise distribution losses
a. Underfloorheatingdistributionboardsorwarmwaterdistributionmanifoldsshouldbelocatedcentrallybetweentheroomsbeingheated,thusminimisingthelengthofinterconnectingservices.
b. Servicepipescarryinghotwatertomoredistantroomsshouldbeinsulatedorroutedthroughconduitstoreducedistributionlossesandtheriskofoverheatingtheroomorfloorfinish.
5.0 System commissioning and corrosion protection
Control of oxidation, biofilm, scale and sludge in warm water heating systems
a. CommissioningwarmwaterfloorheatingsystemsshouldbecarriedoutinaccordancewithBSEN1264-4.Evenwhereplastictubescontainoxygengasbarriers,thecontrolofcorrosioninmixedproductheatingsystemsmustbeaddressedcarefully.
b. Aftertestingandflushingwithcleanwater,thesystemcirculatingfluidshouldbetreatedwithasuitablecorrosioninhibitorapprovedbythetubemanufacturerandcomplyingwithBS7593:2006orDIN4726(2008-2010),andappliedstrictlyinaccordancewiththeadditivemanufacturer’sinstructions.
Standards
BSEN1264-4:2009Water based surface embedded heating and cooling systems. Installation.
BS7593:2006Code of practice for treatment of water in domestic hot water central heating systems.
DIN4726(2008-2010)Warm water surface heating systems and radiator connecting systems. Plastic piping systems and multi layer piping systems.
InhibitorsshouldbeBuildCertapprovedorequivalent.
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Table 33 Recommended minimum standards for construction and control of electric underfloor heating systems
Minimum standard
Electric storage systems with individual room or programmable thermostats and low tariff anticipatory controls
1.0 Construction
a. Electriccableunderfloorheatinglowtariffnightenergystoragesystemsshouldhavea65mmminimumthicknessscreedforcorrectoperation.
b. Principalroomscontaining80%floorareashouldbeassignedtolowtariffheatingcablesand20%ofthefloorareashouldbeassignedtoeitherdirect-actingperimeterheatingcablesorsystemssuchasceilingorpanelheatersinordertomaximiseenergyefficiency.
Supplementary information
Otherareasshouldbeassignedaslowtariffheatingcablesonly(subjecttoheatrequirements).
Bathroomsandseparatekitchensmayhavedirect-actingheatingcables(subjecttoheatrequirements).
2.0 Controls
a. Anticipatorycontrollersshouldbeinstalledcontrollinglowtariffinputchargewithexternaltemperaturesensingandfloortemperaturesensing.
b. Programmableroomthermostatswithanoverridefeatureshouldbeprovidedforalldirect-actingzonesofthesystemwithairandfloortemperaturesensingcapabilitiestobeusedindividuallyorcombined.
Supplementary information
Anticipatorycontrollers(i.e.weathercompensators)reducenightenergystorageasafunctionofexternaltemperature.
Electric cable, direct-acting (non-storage) systems with individual room timer or thermostat control in screeded floors
3.0 Construction
a. Direct-actingelectricunderfloorheatingcablesshouldbeinstalledwithinscreedsofthicknessnotexceeding60mm.
b. AllheatedfloorsshouldbeinsulatedinaccordancewithTable32.
4.0 Controls
a. Programmableroomthermostatswithamanualoverridefeatureforallheatingzoneswithairorfloortemperaturesensingcapabilitiesshouldbeusedindividuallyorcombined.
Electric cable, direct-acting systems with individual room timer or thermostat control in timber floors
5.0 Construction
a. Direct-actingelectricunderfloorheatingcablesinstalledbelowfloorboardsinvoidsbetweenfloorjoistsshouldbeinsulatedinaccordancewithTable32.
6.0 Controls
a. Programmableroomthermostatswithamanualoverridefeatureshouldbeprovidedtocontrolspacetemperatureandlimitfloorvoidtemperatureforsafetyandcomfortineacharea.
Under-tile electric floor heating systems
7.0 Construction
a. Direct-actingelectricunderfloorheatingcablesshouldbeprovidedwithapre-fabricatedmattress,orequivalentIEC60800:2009approvedheatingcableproduct,ofthicknesslessthan4mmencapsulatedintilebeddingadhesiveormortar,belowaceramicorotherequivalentfloorfinishonathermallyresistiveinsulationlayerasinTable321.0b.
8.0 Controls
a. Programmableroomthermostatswithamanualoverridefeatureshouldbeprovidedtocontrolspacetemperatureandlimitfloortemperatureforsafetyandcomfortineacharea.
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Section 8: Mechanical ventilation
8.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofmechanicalventilationsystemsindwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
Theguidancecoversthefollowingtypesofmechanicalventilation:
• intermittentextract
• continuousextract
• continuoussupply
• continuoussupplyandextractwithheatrecovery.
8.2 Energy efficiency of mechanical ventilation systemsMechanicalventilationsystemsshould:
a. followtheguidanceintheDCLGDomestic Ventilation Compliance Guide (availableatwww.planningportal.gov.uk/approveddocuments/PartF)
b. meettheminimumstandardsforspecificfanpower,heatrecoveryefficiencyandcontrolsinTable34
c. complywithEuropeanCommissionRegulationNo327/2011implementingDirective2009/125/ECwithregardtoecodesignrequirementsforfansdrivenbymotorswithanelectricinputpowerbetween125Wand500kW.
Table 34 Recommended minimum standards for mechanical ventilation systems
Minimum standard
1.0 Fan power
a. Mechanicalventilationsystemsshouldbedesignedtominimiseelectricfanpower.Thespecificfanpower(SFP)shouldbenotworsethan:
i. 0.5W/(l.s)forintermittentextractventilationsystems
ii. 0.7W/(l.s)forcontinuousextractventilationsystems
iii.0.5W/(l.s)forcontinuoussupplyventilationsystems
iv. 1.5W/(l.s)forcontinuoussupplyandextractwithheatrecoveryventilationsystems.
2.0 Heat recovery efficiency
a. Theheatrecoveryefficiencyofbalancedmechanicalventilationsystemsincorporatingheatrecoveryshouldbenotworsethan70%.
3.0 Controls
a. Controlsmaybemanual(i.e.operatedbytheoccupant)orautomatic.
Supplementary information
GPG268Energy efficient ventilation in dwellings – a guide for specifiers.
British Standards
BSEN15232:2012Energy performance of buildings. Impact of building automation, controls and building management.
Section 8: Mechanical ventilation
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Section 9: Heat pumps
Section 9: Heat pumps
9.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofheatpumpsystemsindwellingsfortheprovisionofspaceheatinganddomestichotwatertomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
Aheatpumpisadevicewhichtakesheatenergyfromalowtemperaturesourceandupgradesittoahighertemperatureatwhichitcanbeusefullyemployedforheatingorhotwater.Heatpumpsmaysupplyallorpartoftheheatingload.
Theguidanceinthissectionappliestothetypesofelectrically-drivenheatpumpinTable35usedastheheatgeneratorinunderfloor,warmairandmediumtemperatureradiatorheatingsystems,etc.
Section 9: Heat pumps
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Table 35 Heat pump technologies
Heat pump typeWarm water and hot water systems Warm air systems
Ground source heat pump (GSHP) systems
HeatenergyisextractedfromthegroundusingclosedpipeloopsburiedhorizontallyintrenchesorinverticalboreholesthatareconnectedbacktotheGSHP.Thefluidcirculatingintheclosedloopisnormallyawater/propyleneglycolantifreezemixtureoracceptedequivalentbutsomedirectexpansionGSHPsuserefrigerant.Openloopsmayalsobeusedtocollectwaterfromanaquiferanddischargeviaaseparateaquiferdownstreamofthewatertableflow;systemsofthistypenormallyrequirepermitsfromtheEnvironmentAgency.Heatextractedfromthegroundmaybesuppliedtoadwellingeitherbyawater-basedheatingsystem(ground-to-waterheatpump)orbyanairdistributionsystem(ground-to-airheatpump).
Ground-to-water Ground-to-air
Water source heat pump (WSHP) systems
Heatenergyisextractedindirectlyfromawatersourceusingclosedpipeloopsasaheatexchanger.Theclosedloopisconnectedbacktothewater-to-waterheatpump.Thewatersourcemaybealake,pondorriverorotherstablewatersource.Thefluidcirculatingintheclosedloopwillnormallybewaterbutawater/propyleneglycoloracceptedequivalentantifreezemixturemaybeused,dependingonoperatingtemperatures.OpenloopsmayalsobeusedsubjecttothepermitsbeingobtainedfromtheEnvironmentAgency.Heatmaybesuppliedtothedwellingeitherbyawater-basedheatingsystem(water-to-waterheatpump)orbyanairdistributionsystem(water-to-airheatpump).
Water-to-water Water-to-air
Air source heat pump (ASHP) systems
Airsourceheatpumpsextractheatdirectlyfromtheambientair.Heatissuppliedtothedwellingeitherbyawater-basedheatingsystem(air-to-waterheatpump)orbyanairdistributionsystem(air-to-airheatpump).Airsourceheatpumpsmaybesinglepackageorsplitsystems.
Air-to-water Air-to-air
Supplementary information
Allheatpumpsystemsareattheirmostefficientwhenthesourcetemperatureisashighaspossible,theheatdistributiontemperatureisaslowaspossibleandpressurelossesinairandwatersystemsarekepttoaminimum.Ifinstalledinanewdwelling,heatpumpsshoulduserefrigerantscomplyingwiththeprovisionsofECRegulationNo2037/2000.HeatpumpsshouldbeCEmarkedinaccordancewithapplicableEUdirectives:e.g.themachinerysafety,lowvoltage,pressureequipmentandelectromagneticcompatibilitydirectives.Ifsummercoolingisprovidedbytheheatpump,itisrecommendedthatcondensatedrainagefromtheindoorunitsisprovided.
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Section 9: Heat pumps
9.2 Key termsCoefficientofperformance(COP)isameasureoftheefficiencyofaheatpumpatspecifiedsourceandsinktemperatures,butmaynotaccuratelyrepresentinstalledperformance:
HeatingCOPheatoutput/powerinput
%COP(COP100)istheheatgeneratorefficiency.
COPismeasuredinaccordancewiththeproceduresinBSEN14511:2013,Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling.
Seasonalcoefficientofperformance(SCOP)istheoverallcoefficientofperformanceoftheheatpumpoverthedesignatedheatingseason.Itmakesgeneralassumptionsabouttheamountofauxiliaryheatingneededtotopupthespaceandwaterheatingavailablefromtheheatpump.
SCOPismeasuredinaccordancewiththeproceduresinBSEN14825:2013,Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Testing and rating at part load conditions and calculation of seasonal performance.
TheNationalCalculationMethodologyforcalculatingcarbondioxideemissionratesfrombuildingsusesSCOP.
Seasonalperformancefactor(SPF)isanothermeasureoftheoperatingperformanceofanelectricheatpumpovertheseason.Itistheratiooftheheatdeliveredtothetotalelectricalenergysuppliedovertheseason,butthereareuptosevendifferentwaystodrawthesystemboundaries.Forexample,SPF
H2
(whichisSCOP)excludesauxiliaryresistanceheatingwhereasSPFH4
includesit–makingalargedifference.
SAP2012calculationsuseSPF–eithermeasuredvaluesforproductslistedintheProductCharacteristicsDatabase,orthedefaultvaluesinTable4aforproductsnotlistedthere.
TheMicrogenerationCertificationSchemeinstallationstandard,MIS3005,usesSPFtocalculatesystemperformance(althoughtheheatpumpproductstandard,MCS007,currentlyspecifiesaminimumCOP).
Seasonalprimaryenergyefficiencyratio(SPEER)isanemergingratingfigurereflectingtheuseofprimaryenergyforalltypesofheatpump,fossilfuelboilerandgas-drivencogenerationtechnologies,aswellashybridsystemswheresolarheatingoraheatpumpisbackedupwithelectricheatingorafossilfuelboiler.
EnergylabellingwiththeSPEERwillbemandatoryfrom2015undertheEnergyLabellingDirective.TestingandratingwillbeinaccordancewithBSEN14825,asforSCOP.
9.3 Warm water and hot water heat pumpsAtthetimeofpreparationofthisguide,EuropeanCommissionRegulationNo206/2012setsstandardsfortheSCOPofelectrically-drivenair-to-airheatpumpswithanoutput12kW.TherearecurrentlynoEuropeanteststandardsforpart-loadtestingofair-to-airheatpumpswithanoutput12kWorforothertypesofheatpump,andtheperformanceofthesemustbespecifiedusingCOPobtainedattheheatingsystemratingconditions.
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Thecurrentrecommendationsinthisguidearethatelectrically-drivenheatpumpsshould:
a. ifair-to-airwithanoutput12kW,haveatleastaSCOP‘D’ratingforthemediantemperaturerangeinBSEN14825
b. orelsehaveaCOPwhichisnotlessthan:
i. 2.5forspaceheatinginnewdwellings
ii. 2.2forspaceheatinginexistingdwellings
iii. 2.0forheatingdomestichotwater
c. meettheminimumstandardsforsupplytemperature,wetsystemradiatorefficiency,installationandcommissioning,hotwaterandcontrolsinTable36forwarmwaterandhotwaterheatpumps
d. meettheminimumstandardsforinstallationandcontrolsinTable37forwarmairheatpumps.
Table 36 Recommended minimum standards for warm water and hot water heat pumps (ground-to-water, water-to-water and air-to-water systems)
Minimum standard Supplementary information
1.0 Supply water temp-eratures and efficiency
Underfloor heating
a. Supplywatertemperaturestotheunderfloorheatingsystemshouldbeintherange30°Cto40°Cfornewbuildingsand30°Cto55°Cforexistingsystems.
SeeSection7ofthisguideonunderfloorheating.
Radiators
b. High-efficiencyradiatorswithhighwatervolumeshouldbeutilised.
c. Supplywatertemperaturetotheradiatorsshouldbeintherange40°Cto55°C.
Spaceheatingmaybesizedtomeetallorpartofthespaceheatingload.Secondaryheatingwillberequirediftheheatpumpissizedtomeetpartofthespaceheatingload.
Fan coil units
d. Supplywatertemperaturetothefancoilunitsshouldbeintherange35°Cto45°C.
Fancoilunitsmaybeutilisedforheatingonlyorforwinterheatingandsummercooling.
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Table 36 Recommended minimum standards for warm water and hot water heat pumps (ground-to-water, water-to-water and air-to-water systems) (continued)
Minimum standard Supplementary information
2.0 Installation and commission-ing
a. Thewaterdistributionsystemshouldbearrangedforreversereturnoperationorarrangedwithalowlossmanifoldsystemtomaximiseefficiencyandeasecommissioningandfuturemaintenance.
b. Pipeworknotcontributingtothespaceheatingshouldbeinsulatedtopreventheatloss,followingtheguidanceintheTIMSAguide.
c. Ifsummercoolingisprovidedbytheheatpump,allwaterdistributionpipeworkshouldbeinsulatedtopreventcondensation,followingtheguidanceintheTIMSAguide.
d. Externalpipeworkbetweenthedwellingandthegroundheatexchangershouldbeinsulated,followingtheTIMSAguidance.
e. Thegroundloopwatercircuitshouldbeprotectedwithanantifreezesolutionandinhibitorasrecommendedbytheheatpumpmanufacturer.
f. Groundloopsshouldbecleanedwithacleaningfluidandbiocideaspartofthecommissioningprocess.
g. Theinternalwaterdistributioncircuitshouldcontainaninhibitorandmaybeprotectedbyanantifreezesolutionasrecommendedbytheheatpumpmanufacturer.
h. Groundloopsshouldbefilledwithaheattransferfluid.Installersshouldalsorefertotheequipmentmanufacturer’sinstallationinstructionsforappropriatetreatmentproductsandspecialrequirementsforindividualappliancemodels.
Design
Apressurisedwaterdistributionsystemwithexpansionvesselisrecommended.
Constantwaterflowshouldbemaintainedthroughtheheatpump.
Pipesizesshouldbeinaccordancewiththemanufacturer’srecommendations.
Installation
Installationshouldbecarriedoutbyaninstallerapprovedbythemanufacturer.
Ifduringinstallationaccesstotherefrigerationcircuitisneeded,acompetentrefrigerationandairconditioningengineerholdingarefrigeranthandlingcertificateandanEngineeringServicesSkillcardshouldcarryoutthework.
Exposedrefrigerationpipeworkshouldbeinsulatedandenclosedinprotectivetrunkingtolimitaccidentaldamage.
Installationofthedwelling’swaterdistributionsystemshouldbeundertakenbyacompetentcentralheatingspecialist.
Guidance and standards
TIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
BSEN378:2008Refrigerating systems and heat pumps.Safety and environmental requirements.
TR30Guide to good practice – heat pumps,HVCA,July2007.
MIS3005Requirements for contractors undertaking the supply, design, installation, set to work, commissioning and handover of microgeneration heat pump systems,DECC.
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Table 36 Recommended minimum standards for warm water and hot water heat pumps (ground-to-water, water-to-water and air-to-water systems) (continued)
Minimum standard Supplementary information
3.0 Domestic hot water (DHW)
a. Forfullheating,theheatpumpandanysupplementarydomestichotwaterheatingshouldbecapableofsupplyingwaterintherange60°Cto65°C.Thisisapplicabletoground-to-water,water-to-waterandair-to-watertypeheatpumps.
b. Iftheheatpumpisnotcapableofsupplyingwateratthesetemperatures,supplementaryheatingshouldbeprovidedandcontrolledasdescribedinothersectionsofthisguide.Controlsshouldincludeanauxiliaryheatingregimeto60°Cormorefordisinfectionpurposes.
c. Thedomestichotwatersystemshouldhavetemperaturecontrol(e.g.atankthermostat)andtimecontroltooptimisethetimetakentoheatthewater.
TheheatpumpmaybeutilisedforallorpartoftheDHWload.DuringtheDHWheatingperiodtheheatpumpmaynotnecessarilybeprovidingheatedwatertothespaceheatingsystem.
4.0 Controls
a. Heatpumpunitcontrolsshouldinclude:
i. controlofwaterpumpoperation(internalandexternalasappropriate)
ii. controlofwatertemperatureforthedistributionsystem
iii. controlofoutdoorfanoperationforair-to-waterunits
iv. defrostcontrolofexternalairsideheatexchangerforair-to-watersystems
v. protectionforwaterflowfailure
vi. protectionforhighwatertemperature
vii. protectionforhighrefrigerantpressure
viii. protectionforairflowfailureonair-to-waterunits.
b. Externalcontrolsshouldinclude:
i. weathercompensationorinternaltemperaturecontrol
ii. timerorprogrammerforspaceheating.
c. Minimumheatpumpflowratesorvolumerequirementsshouldbemet.Ifallzonesarethermostaticallycontrolled,thenabufferwouldbeanacceptablemethodofcompliance.
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Table 37 Recommended minimum standards for warm air heat pumps (ground-to-air, water-to-air and air-to-air systems)
Minimum standard Supplementary information
1.0 Installation
a. Minimumclearancesadjacenttoallairflowpaths,asrecommendedbythemanufacturer,shouldbemaintained.
b. Pipesizesshouldbeinaccordancewiththemanufacturer’srecommendations.
c. Therefrigerantpipeworkonsplitsystemsshouldbeinsulatedinlinewiththemanufacturer’srecommendations.
d. Ifsummercoolingisprovidedbytheheatpump,provisionshouldbemadeforcondensatedrainagefromtheindoorterminalunits.
e. Forground-to-airandwater-to-airsystemsallexternalpipeworkbetweenthedwellingandtheexternalheatexchangershouldbeinsulatedfollowingTIMSAguidance.
f. Forground-to-airandwater-to-airsystemsconstantwaterflowshouldbemaintainedthroughtheheatpump.
Installationshouldbecarriedoutbyaninstallerapprovedbythemanufacturer.
Installationthatrequiresaccesstotherefrigerationcircuit,ortheconnectionofsplitsystems,shouldbecarriedoutbyacompetentrefrigerationandairconditioningengineerholdingarefrigeranthandlingcertificateandanEngineeringServicesSkillcard.
TIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
2.0 Controls
a. Heatpumpunitcontrolsshouldinclude:
i. controlofroomairtemperature(ifnotprovidedexternally)
ii. controlofoutdoorfanoperationforair-to-airunits
iii. defrostcontrolofexternalairsideheatexchangerforair-to-airsystems
iv. controlforsecondaryheating(iffitted)onair-to-airsystems
v. controlofexternalwaterpumpoperationforground-to-airandwater-to-airsystems
vi. protectionforhighrefrigerantpressure
vii. protectionforindoorairflowfailure
viii. protectionforexternalairflowfailureonair-to-airunits
ix. protectionforwaterflowfailureonground-to-airandwater-to-airsystems.
b. Externalcontrolsshouldinclude:
i. weathercompensationorinternaltemperaturecontrol
ii. timerorprogrammerforspaceheating.
c. Minimumheatpumpflowratesorvolumerequirementsshouldbemet.Ifallzonesarethermostaticallycontrolled,thenabufferwouldbeanacceptablemethodofcompliance.
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Supplementary information
Guidance
MicrogenerationCertificationSchemestandardMIS3005Requirements for contractors undertaking the supply, design, installation, set to work, commissioning and handover of microgeneration heat pump systems.
MicrogenerationCertificationSchemestandardMIS3007Product certification scheme requirements – heat pumps.
Heat emitter guide for domestic heat pumps.Availablefromhttp://www.microgenerationcertification.org/mcs-standards/installer-standards.
Design of low-temperature domestic heating systems – A guide for system designers and installers.FB59,IHSBREPress.Availablefromwww.brebookshop.com.
CE82EnergyEfficiencyBestPracticeinHousing:Domestic ground source heat pumps: design and installation of closed-loop systems.
HeatPumpAssociationdatasheetAir-to-water heat pumps.
HVCATR30Guide to good practice: Heat pumps.
Standards
BSEN15450:2007Heating systems in buildings. Design of heat pump heating systems.
BSEN15316-4-2:2008Heating systems in buildings. Methods for calculation of system energy requirements and system efficiencies.Space heating generation systems, heat pump systems.
BSEN378-1:2008+A2:2012Refrigerating systems and heat pumps. Safety and environmental requirements. Basic requirements, definitions, classification and selection criteria.
BSEN378-2:2008+A2:2012 Refrigerating systems and heat pumps. Safety and environmental requirements. Design, construction, testing, marking and documentation.
BSEN378-3:2008+A1:2012Refrigerating systems and heat pumps. Safety and environmental requirements. Installation site and personal protection.
BSEN378-4:2008+A1:2012Refrigerating systems and heat pumps. Safety and environmental requirements. Operation, maintenance, repair and recovery.
ISO13256-1:1998Water-source heat pumps. Testing and rating for performance. Water-to-air and brine-to-air heat pumps.
ISO13256-2:1998Water-source heat pumps. Testing and rating for performance. Water-to-water and brine-to-water heat pumps.
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Section 10: Comfort cooling
Section 10: Comfort cooling
1 0.1 Scope of guidanceThissectionprovidesguidanceonthespecificationoffixedmechanicalcomfortcoolingsystemsandfansindwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
(Dwellingsshouldalwaysbedesignedtoavoidorminimisetheneedforcoolingthroughtheappropriateuseofsolarcontrol,secureventilationandthermalmass.)
10.2 Air-cooled and water-cooled air conditionersCoolingsystemsinnewandexistingdwellingsshould:
a. meettheminimumstandardsforefficiencyinTable38
b. becontrolledtopreventsimultaneousheatingandcoolingofthesamespacewithinthedwelling
c. complywithEuropeanCommissionRegulationNo327/2011forfansdrivenbymotorswithanelectricinputpowerbetween125Wand500kW,andRegulationNo206/2012forsystemswithacoolingcapacityofupto12kW,bothimplementingDirective2009/125/ECwithregardtoecodesignrequirementsforenergy-relatedproducts.
Table 38 Recommended minimum standards for air conditioner efficiency
Minimum standard Supplementary information
a. Air-cooledairconditionersworkingincoolingmodeshouldhaveanEERgreaterthan2.4.
b. Water-cooledairconditionersworkingincoolingmodeshouldhaveanEERgreaterthan2.5.
c. FixedairconditionersshouldhaveanenergyefficiencyclassificationequaltoorbetterthanClassCinSchedule3ofthelabellingschemeadoptedunderTheEnergyInformation(HouseholdAirConditioners)(No2)Regulations,SI2005/1726.
Installationshouldbecarriedoutbyaninstallerapprovedbythemanufacturerorsupplier.Theinstallershouldbeacompetentrefrigerationandairconditioningengineerwithavalidrefrigeranthandlingcertificate.
Exposedrefrigerationpipeworkshouldbeinsulatedandenclosedinprotectivetrunkingtolimitaccidentaldamage.
See:www.eurovent-certification.com
British Standards
BSEN14511-2:2013Airconditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Test conditions.
BSEN14511-4:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Requirements.
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Section 11: Solar water heating
11.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofsolarwaterheatingfordwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
Theguidanceinthissectioncoversindirectsolarsystemswithacollectorareaoflessthan20m2andsolarheatedwaterstorageoflessthan440litres.Itdoesnotcover‘direct’solarsystems18orsystemsintendedtocontributeexclusivelytospaceheatingorsystemsprovidingheatexclusivelytoheatswimmingpools.Itshouldbeusedinconjunctionwiththeguidanceonwaterheatingcontainedinthefuel-basedsectionsofthisguide.
11.2 Indirect systemsIndirectsolarheatingsystemsinstalledasnewsystemsandreplacementsystemsshouldmeettheminimumstandardsfor:
a. collectorcertification,identificationandtesting,collectorprimarylooptransferfluid,circulationpumppower,heat-exchangersizing,systemcontrol,solarpre-heatedwaterstorageandsystempreparationinTable39
b. systemlabellingandcommissioninginTable40
c. insulatingpipesinasolarprimarysysteminTable41.
Supplementary information
Whenworkiscarriedoutonanexistingindirectsolarhotwatersystem,itisrecommendedthatthesystemcontrolsandinsulationshouldbeupgradedinlinewiththestandardsfornewsystems.
Table 39 Recommended minimum standards for indirect solar water heating
Minimum standard Supplementary information
1.0 Allowance for collector shading
a. Nominimumprovision. Solarcollectorsshouldbesitedinunshadedlocationswhereverpossible.Wherethisisunachievableorincasesofsignificantorheavyshadingorsignificantvariancetotheoptimumorientationandtilt(i.e.normalpitchroofsfacingbetweenSEandSW),thenanallowanceforthelossofperformanceshouldbemadewhensizingthecollectorareaaccordingtothefactorsindicatedinSAP2012AppendixH.
18 TheMicrogenerationCertificationSchemeStandardMIS3001includesguidanceonsolarheatingsystemswithadedicatedsolarvolumethatisbelowtheminimumrecommendedforindirectsystems.SAP2012AppendixHsetsoutrulesforestimatingtheannualenergyperformanceofsolarheatingsystems,includingdirectsystems.
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Table 39 Recommended minimum standards for indirect solar water heating (continued)
Minimum standard Supplementary information
2.0 Solar collector certification
a. Collectorsshouldbeindependentlycertifiedtocomplywithallrequiredtestsforsafetyandthermalperformance,andforreportingandidentificationaccordingtoBSEN12975-1:2006+A1:2010Thermal solar systems and components. Solar collectors. General requirements.
Copiesofthefulltestreportshouldbemadeavailableuponrequest.
3.0 Primary circuit fluid
a. Thetransferfluidinthecollectorprimaryloopshouldbechosensoasnottodepositlimescale,sludge,iceorothersolidsthatcouldeitherrestrictcirculationorimpairtherateofheattransferwithintheabsorber.
Insecondarysystems,measurestoreducetheformationoflimescaleshouldbeconsideredsothatperformanceisnotsignificantlyaffected.
4.0 Circulation pump power
a. Theelectricalinputpoweroftheprimarypumpinthesolarsystemshouldbelessthan50Wor2%ofpeakthermalpowerofcollector,whicheveristhehigher.
5.0 Heat-exchanger sizing
a. Theheatexchangerbetweenasolarprimaryandsecondarysystemshouldbesizedsothatnotlessthan0.1m2orequivalentofheatexchangerareaisprovidedper1m2ofsolarcollectornetabsorberarea.
Aheatexchangerreducesthepossibilityofclogginganddepositionduetodirt,scaleorsimilarimpuritiesthatcouldreducethesystemperformance.
Heatexchangersandstoreconnectionsshouldbesizedandlocatedtopromotealowreturntemperaturetothesolarcollector.Solarheatexchangersareoftensizedlargerthanthoseusuallyusedongas-oroil-basedprimarysystemsowingtothelowertemperatureoftransfer.
6.0 System control
a. Solardomestichotwater(DHW)systemcontrolsshouldbefittedto:
i. maximisetheusefulenergygainfromthesolarcollectorsintothesystem’sdedicatedstorage
ii. minimisetheaccidentallossofstoredenergybythesolarDHWsystem,whetheroriginatingfromsolarcollectors,coldintakeorauxiliaryheatsources
iii.ensurethathotwaterproducedbyback-up(auxiliary)heatsourcesisnotusedwhenadequategradesolarpre-heatedwaterisavailable
iv.provideameansofcontrolconsistentwiththesolarsystembeinghydraulically(inherently)secureagainsttheadverseeffectsofexcessiveprimarytemperaturesandpressures
v. whereaseparateDHWheatingapplianceispre-heatedbyasolarsystem,controltheappliancewherepossiblesuchthatnoextraheatisaddedifthetargettemperatureisalreadysatisfiedfromthepre-heatvessel
vi.informtheenduserofthesystem’scorrectfunctionandperformanceatalltimes.
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Table 39 Recommended minimum standards for indirect solar water heating (continued)
Minimum standard Supplementary information
7.0 Solar pre-heated water storage
a. Ventedcopperhotwaterstoragevesselsshouldcomplywiththeheatlossandback-upheatingheatexchangerrequirementsofBS1566-1:2002Copper indirect cylinders for domestic purposes. Open vented copper cylinders. Requirements and test methods.
b. UnventedhotwaterstoragesystemproductsshouldcomplywithBSEN12897:2006oranequivalentstandard.
c. Primarystoragesystemsshouldmeettheinsulationrequirementsofsections4.3.1or4.3.2oftheHotWaterAssociationPerformance specification for thermal stores.
VentedcopperhotwatercylindersshouldcarryclearlabellingontheproductsuchasaBSIKitemark,registeredfirmstatusorreferencetoanequivalentqualitycontrolscheme.
VentedcylinderswhicharenotofcopperconstructionshouldbelabelledascomplyingwiththeheatlossandheatexchangerrequirementsofBS1566-1:2002.
Duetothehigherthannormalstoragetemperaturesinprimarystores,itisveryimportantthattheyarewellinsulated.
8.0 Volume of solar pre-heated water
a. Theratioofsolarheatedwaterstoragevolumetocollectorareashouldbeasfollows:
i. Thededicatedsolarstoragevolume,Vs,shouldbeat
least25litres(orequivalentheatcapacity)pernetsquaremetreofthesolarcollectorabsorberarea.
ii. Alternatively,Vsshouldbeavolume(orequivalent
heatcapacity)whichisequivalenttoatleast80%ofthedailyhotwaterdemand,V
d(asdefinedby
SAP2012).
Collectorareaismeasuredaseffectiveapertureornetabsorberarea,whicheverissmaller.
Aseparatepre-heatstoragevesselshouldbeconsideredwhereverpossible.
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Table 39 Recommended minimum standards for indirect solar water heating (continued)
Minimum standard Supplementary information
9.0 System preparation and water treatment
New build
a. Solarprimarycircuitsshouldbethoroughlycleanedwithanappropriatecleanerandflushedthroughwithsolarheattransferfluidbeforefillingwiththesolarheattransferfluid.
b. Systemsshouldbefilledwithaheattransferfluidcontainingavolatileinhibitorpackage,capableofprotectingthesystemfromfrostandcorrosionatalloperatingtemperatures.
c. Installersshouldrefertotheequipmentmanufacturer’sinstallationinstructionsforappropriatetreatmentproductsandspecialrequirementsforindividualappliancemodels.
d. Wheremainswaterisusedtofillthesolarprimarycircuitandthetotalwaterhardnessexceeds200partspermillion,provisionshouldbemadetoreducethelimescale.
Existing installations
e. Solarthermalsystemsshouldbecleanedwithanappropriatecleanerformulatedtoremovebuild-upofdegradationfilmsfromexhaustedheattransferfluids,thenflushedthroughwithfreshsolarheattransferfluid.
f. Systemsshouldbefilledwithaheattransferfluidcontainingavolatileinhibitorpackage,capableofprotectingthesystemfromfrostandcorrosionatalloperatingtemperatures.
g. Installersshouldrefertotheequipmentmanufacturer’sinstallationinstructionsforappropriatetreatmentproductsandspecialrequirementsforindividualappliancemodels.
PartsofBS7593:2006Code of practice for treatment of water in domestic hot water central heating systemsmayassistinflushingandcleaningprocedures.
Legionnaire’s disease: The control of legionella bacteria in water systems.Approvedcodeofpracticeandguidance,HSEBooks.
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Table 40 Recommended minimum standards for labelling, commissioning and documentation for solar hot water systems
Minimum standard Supplementary information
1.0 Labelling of solar collectors and hot water stores
a. AllsolarcollectorsshouldhaveavisibleanddurablelabeldisplayingallinformationrequiredaccordingtoBSEN12975-1:2006+A1:2010,andincludingatleastthefollowing:
i. nameofmanufacturer
ii. collectortype
iii. serialnumber
iv. yearofproduction
v. grossareaofcollector
vi. apertureareaofcollector
vii. netabsorberareaofcollector
viii. maximumoperationpressure
ix. stagnationtemperatureat1000W/m2and30°Cambient
x. volumeofheattransferfluid
xi. weightofemptysolarcollector.
b. Allhotwaterstoragevesselsshouldcarryalabelwiththefollowinginformation:
i. nameofmanufacturer
ii. nominaloverallcapacityinlitres
iii. dedicatedsolarcapacityinlitres
iv. standingheatlossinkWh/day
v. typeofvessel
vi. back-upheatingheatexchangerperformanceinkW(wherepresent)
vii. solarheatingheatexchangerperformanceinkW.
Inadditiontotheminimumprovisionforlabellingofhotwaterstoragevessels,labellingwiththefollowinginformationisalsorecommended:
• Totalnetfluidcontentofsecondaryvolumenormallyheatedbyeachheatexchanger,wherepresent(1.0litre).
• Thetype,fluidcontent,maximumpressureandsurfaceareaofallheatexchangers.
2.0 Commis-sioning
a. Asignedanddatedcommissioningcertificateshouldbecompletedtoconfirmtheequipmenthasbeencorrectlyinstalledandtorecordkeysafetyandoperationalfeatures.
b. Asaminimum,thecommissioningcertificateshouldrecordthefollowingdetailsofthesolarsystem:
i. netorapertureareaofsolarcollector
ii. minimumambienttemperaturewithoutfreezedamagetocomponents
iii. locationofdeviceandmethodforcontrollingover-pressure
iv. locationoftheelectricalisolatingswitch
v. typeofcirculationfluid
vi. circulationrateofcollectorcircuit
vii. locationofdeviceforprotectingagainstoverheatingofsolarheatedwater.
Asignedcommissioningcertificate,certifyingthattheequipmentissafe,legalandfitforitsintendedpurpose,shouldbehandedovertothedwellingowneroruserasapplicable.
AseparatecertificateisrequiredtocovertheinstallationandcommissioningofthehotwaterstoragevesselsandapplianceswithinasolarDHWsystem.
Acommissioningengineershouldbeacompetentpersonwhocanpersonallytestifybysignatureanddatethattheequipmenthasbeencommissioned.
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Table 40 Recommended minimum standards for labelling, commissioning and documentation for solar hot water systems (continued)
Minimum standard Supplementary information
3.0 Document-ation
Informationprovidedtothedwellingownerorusershouldinclude:
• usermanual
• warrantyinformation
• arecommendedmaintenanceschedule
• commissioningcertificate
• fullcontactdetailsoftheinstaller.
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Table 41 Recommended minimum standards for insulation of pipework in solar hot water systems
Minimum standard Supplementary information
a. Allpipesofasolarprimarysystemshouldbeinsulatedthroughoutthelengthofthecircuit.
b. Allotherpipesconnectedtohotwaterstoragevessels,includingtheventpipe,shouldbeinsulatedforatleast1metrefromtheirpointsofconnectiontothecylinder,orinsulateduptothepointwheretheybecomeconcealed.
c. PipesshouldbeinsulatedwithappropriatelylabelledmaterialsandinlinewiththeTIMSAguide.
d. HeatlossvaluesshouldnotexceedthevaluesintheSupplementaryinformationcolumn.
Theinsulationshouldbesuitablyratedforthemaximumforeseeablepipetemperatureapplicable,andwhereexternalalsoberesistanttoverminattackandclimaticdegradation.
Inadwellingthatalreadyhasasolarhotwatersystem,itisrecommendedthattheinsulationshouldbeupgradedinlinewiththeseminimumprovisionswheresignificantwork,suchaschangeofsolarstorage,iscarriedout.
Afully-filledordrainbacksolarhotwatersystemcanhaveapipeservicetemperatureof150°C.Theinsulationmaterialshouldbespecifiedtoaccommodatethistemperature.AnEPDMbasedrubberwouldnormallybeaminimumrequirementforsuchanapplication.Anyinsulationspecifiedshouldbebetterthan0.044W/(m.K)at40°Cmeanandtheinsulationdiametershouldbe87%ofthepipediameter.
Pipe outside diameter (mm)8
1012152228354254
Maximum heat loss (W/m)7.067.237.357.899. 1 2
10.0711 .0812. 1 914. 1 2
Inassessingthethicknessofinsulationrequired,standardisedconditionsshouldbeassumedinallcompliancecalculations,basedonahorizontalpipeat40°Cinstillairat15°C.
FurtherguidanceonconvertingheatlosslimitstothicknessesofinsulationforspecificthermalconductivitiesisavailableintheTIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.
Insulation for pipework in unheated areas
Itmaybenecessarytoprotectwater-carryingpipeworkinunheatedareasagainstfreezing.Furtherguidanceisavailablein:
• BS5422:2009Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range of -40°C to +700°C.
• BREReportNo262Thermal insulation: avoiding risks, 2002edition.
Further information
MicrogenerationCertificationSchemestandardMIS3001Requirements for contractors undertaking the supply, design, installation, set to work, commissioning and handover of solar heating microgeneration systems.
EnergyEfficiencyBestPracticeinHousingCE131Solar water heating systems. Guidance for professionals, conventional indirect models.
CIBSESolar heating design and installation guide.
CE51/GIL59Central Heating System Specifications (CHeSS),2005.
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Section 12: Lighting
Section 12: Lighting
12.1 Scope of guidanceThissectionprovidesguidanceonthespecificationoffixedinternalandexternallightingfornewandexistingdwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
12.2 Key termsCircuit-wattmeansthepowerconsumedinlightingcircuitsbylampsand,whereapplicable,theirassociatedcontrolgear(includingtransformersanddrivers)andpowerfactorcorrectionequipment.
Lightfittingmeansafixedlightorlightingunitthatcancompriseoneormorelampsandlampholders,controlgearandanappropriatehousing.Thecontrolgearmaybeintegratedinthelamporlocatedelsewhereinorneartothefixedlight.
Fixedexternallightingmeanslightingfixedtoanexternalsurfaceofthedwellingsuppliedfromtheoccupier’selectricalsystem.Itexcludeslightingincommonareasofblocksofflatsandinothercommunalaccessways.
12.3 Internal and external lightingFixedinternalandexternallightingshouldmeettheminimumstandardsforefficacyandcontrolsinTable42.
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Table 42 Recommended minimum standards for fixed internal and external lighting
Minimum standard Supplementary information
Fixed internal lighting
a. Intheareasaffectedbythebuildingwork,providelowenergylightfittings(fixedlightsorlightingunits)thatnumbernotlessthanthreeperfourofallthelightfittingsinthemaindwellingspacesofthoseareas(excludinginfrequentlyaccessedspacesusedforstorage,suchascupboardsandwardrobes).
b. Lowenergylightfittingsshouldhavelampswithaluminousefficacygreaterthan45lamplumenspercircuit-wattandatotaloutputgreaterthan400lamplumens.
c. Lightfittingswhosesuppliedpowerislessthan5circuit-wattsareexcludedfromtheoverallcountofthetotalnumberoflightfittings.
Lightfittingsmaybeeither:
• dedicatedfittingswhichwillhaveseparatecontrolgearandwilltakeonlylowenergylamps(e.g.pinbasedfluorescentorcompactfluorescentlamps),or
• standardfittingssuppliedwithlowenergylampswithintegratedcontrolgear(e.g.bayonetorEdisonscrewbasecompactfluorescentlamps).
LightfittingswithGLStungstenfilamentlampsortungstenhalogenlampswouldnotmeetthestandard.
TheEnergySavingTrustpublicationGIL20Low energy domestic lightinggivesguidanceonidentifyingsuitablelocationsforfixedenergyefficientlighting.
Asingleswitchshouldnormallyoperatenomorethansixlightfittingswithamaximumtotalloadof100circuit-watts.
Fixed external lighting
Wherefixedexternallightingisinstalled,providelightfittingswiththefollowingcharacteristics:
a. Either:
i. lampcapacitynotgreaterthan100lamp-wattsperlightfitting,and
ii. alllampsautomaticallycontrolledsoastoswitchoffafterthearealitbythefittingbecomesunoccupied,and
iii.alllampsautomaticallycontrolledsoastoswitchoffwhendaylightissufficient.
b. Or:
i. lampefficacygreaterthan45lumenspercircuit-watt,and
ii. alllampsautomaticallycontrolledsoastoswitchoffwhendaylightissufficient,and
iii.lightfittingscontrollablemanuallybyoccupants.
Supplementary information
British Standards
BSEN15193:2007Energy performance of buildings. Energy requirements for lighting.
Other related documents
CE80Domestic lighting innovations,EnergyEfficiencyBestPracticeinHousing.
CE61Energy efficient lighting – guidance for installers and specifiers,EnergySavingTrust.
EP84Housing for people with sight loss,ThomasPocklingtonTrustDesignGuide.
IP412Making the most of your sight: Improve the lighting in your home,RNIBandThomasPocklingtonTrust.
Energy Saving Trust best practice standards
TheEnergySavingTrustsetsbestpractice‘EnergySavingRecommended’(ESR)standardsforlampsthatcovernotonlyenergyefficiency,butalsootheraspectsofqualityincludingcolourrendering,warm-uptime,productlifeandpowerfactor.ItisadvisabletoinstallonlyESRlowenergylampsindwellings.
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Section 13: Micro-combined heat and power
Section 13: Micro-combined heat and power
13.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofmicro-combinedheatandpower(micro-CHP)packagesfordwellingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
Theguidancecoversmicro-CHPsystemswithanelectricaloutputlessthan5kWewhichare:
• heat-led
• capableofexportingelectricitytothegrid,and
• controlledinsuchawayastoavoidheatdumping.
13.2 Key termsHeatingplantemissionrate(HPER)istheannualcarbondioxideemissionsfromfuelandpowerconsumedbytheheatingplant,offsetbytheemissionssavedasaresultofanyelectricitygeneratedbytheheatingplant,dividedbytheheatoutputoverayear.ItismeasuredinunitsofkgofcarbondioxideperkWh.TocalculateHPERitisnecessarytoknowtheplantsizeratio.Note:TheHPERincludesanyauxiliaryspaceandwaterheatingthatmaybenecessary,i.e.itrepresentstheperformanceofallheatingplantneededtoprovidespaceandwaterheatingservicetothebuilding,assumingastandarddemandpattern.
Plantsizeratio(PSR)isdefinedasthenominalheatoutputoftheheatingplantdividedbythedesignheatloss(theaverageheatlossofthebuildingonacolddaywithatemperaturedifferentialof24.2°C).Note:Foragivenheatdemand,thePSRdeterminesthepart-loadconditionfortheheatingplant.
13.3 Micro-CHP systemsa. Fornewsystems, theHPERofthemicro-CHPpackage(calculatedasinsub-paragraphc.below)should
benogreaterthanthecarbondioxideemissionfactorforthefueldividedbytheminimumefficiencyforaregularboilerusingthatfuel,atthePSRdeterminedasinsub-paragraphb.below.ThedesignheatlossofthedwellingshouldbecalculatedusingtheEnergySavingTrust’sWhole house boiler sizing method for houses and flats19.
b. ThePSRforthemicro-CHPsystemwhenoperatingintheintendeddwellingshouldbecalculatedasdefinedinparagraph13.2above.
c. TheHPERofthemicro-CHPsystemshouldbecalculatedatthePSRdeterminedinsub-paragraphb.above,usingthemethodologysetoutinDECC’sAnnualPerformanceMethod(APM)20andtheperformancedataforthemicro-CHPpackageestablishedbytestingaccordingtoBSIPAS6721.
19 EnergySavingTrustCE54Whole house boiler sizing method for houses and flats.ThisisaninteractivecalculatoravailablefromtheEnergySavingTrustatwww.energysavingtrust.org.uk/housingbuildings/publications.ThedesignheatlossinkWisthebasicdesignheatlossinboxU(fromthe2010edition).
20 Method to evaluate the annual energy performance of micro-cogeneration heating systems in dwellings(APM),SAP2012revision,DECC.Availablefromwww.bre.co.uk/sap2012.21 BSIPAS67:2008Laboratory tests to determine the heating and electrical performance of heat-led micro-cogeneration packages primarily intended for heating dwellings.
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Supplementary information
British Standards
BSEN15316-4-4:2007Heating systems in buildings. Method for calculation of system energy requirements and system efficiencies. Heat generation systems, building-integrated cogeneration systems.
Other documents
AppendixNofSAP2012Method to evaluate the annual energy performance of micro-cogeneration heating systems in dwellings.
BSRIABG2/2007CHP for existing buildings: Guidance on design and installation.
MicrogenerationCertificationSchemestandard,MIS3007-2Requirements for contractors undertaking the design, supply, installation, set to work, commissioning and handover of a domestic hot water system containing an electricity-led micro-cogeneration package.
Connecting a microgeneration system to a domestic or similar electrical installation (in parallel with the mains supply),BestPracticeGuide,theElectricalSafetyCouncil.
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Section 14: Heating system circulators
Section 14: Heating system circulators
14.1 Scope of guidanceThissectionprovidesguidanceonthespecificationofheatingsystemglandlesscirculators,bothstandaloneandintegratedinproducts,tomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.
14.2 CirculatorsHeatingsystemglandlesscirculatorsupto2.5kW,providedwithnewsystemsorasreplacementsinexistingsystemsindwellings,shouldmeettheminimumstandardsforenergyefficiencyinTable43.
Table 43 Recommended minimum standards for heating system glandless circulators
Minimum standard Supplementary information
InaccordancewithEuropeanCommissionRegulationNo622/2012(amending641/2009)implementingDirective2005/32/ECwithregardtoecodesignrequirementsforglandlesscirculatorsupto2.5kW:
a. From1January2013,standaloneglandlesscirculators,otherthanthosespecificallydesignedforprimarycircuitsofthermalsolarsystemsandofheatpumps,shouldhaveanEnergyEfficiencyIndex(EEI)nogreaterthan0.27.
b. From1August2015,standaloneglandlesscirculatorsandglandlesscirculatorsintegratedinproductsshouldhaveanEnergyEfficiencyIndex(EEI)nogreaterthan0.23.
Furtherinformationandguidance,includingalistofapprovedglandlessdomesticcirculators,isavailableatwww.bpma.org.uk.
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Appendix A: Abbreviations
APM AnnualPerformanceMethodASHP AirsourceheatpumpBS BritishStandardBSI BritishStandardsInstituteCHeSS CentralHeatingSystemSpecificationsCHP CombinedheatandpowerCO
2 Carbondioxide
COP CoefficientofperformanceDCLG DepartmentforCommunitiesandLocalGovernmentDECC DepartmentofEnergyandClimateChangeDHW DomestichotwaterEEI EnergyEfficiencyIndexEER EnergyefficiencyratioEN EuropeanNorm(standard)ESR EnergySavingRecommendedGSHP GroundsourceheatpumpHPER HeatingplantemissionrateHVAC Heating,ventilationandairconditioningLPG LiquifiedpetroleumgasPAS PubliclyAvailableSpecificationPCDB ProductCharacteristicsDatabasePSR PlantsizeratioRHI RenewableHeatIncentiveSAP StandardAssessmentProcedureSCOP SeasonalcoefficientofperformanceSEDBUK SeasonalEfficiencyofDomesticBoilersintheUKSEER SeasonalenergyefficiencyratioSFP SpecificfanpowerSI StatutoryInstrumentSPEER SeasonalprimaryenergyefficiencyratioSPF SeasonalperformancefactorTER TargetcarbondioxideemissionrateTRV ThermostaticradiatorvalveWSHP Watersourceheatpump
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